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Synthetic approach to analogues of 19-norsteroids with an acyclic side chain
SYNTHETIC APPROACH TO ANALOGUES OF 19-NORSTEROIDS WITH AN ACYCLIC SIDE CHAIN Pavel Dra~ar,. Vladimfr Pouzar,. Ivan Cern~,. Miroslav Havel,. Vera V. Egorova, b Sophia N Ananchenko, b Igor V Torgov, b and Franti~ek Ture~ek c alnstitute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Praha, Czechoslovakia; bM.M Shemyakin Institute of Bio-organic Chemistry, Academy of Sciences of the U S S R., 117998 Moscow, U S SR.; and CHeyrovskyInstitute of Physical Chemistry and Electrochemistw, Czechoslovak Academy of Sciences, 121 38 Praha, Czechoslovakia Correspondingauthor: PavelDra§ar ReceivedSeptember15, 1987 RevisedFebruary25, 1988
ABSTRACT Racemic 14#-hydroxy-3-methoxy-8~,9~-1,3,5(10)-estratriene-17-one (I), obtained by t o t a l synthesis, was c o n v e r t e d i n t o a d e r i v a t i v e with alkoxycarbonylethylenic side chain, rac-(20E)-21-methoxycarbonyl-19nor-8~,9~-pregna-1,3,5(10),20-tetraene-3,14~-diol 3-methyl ether (XII) using two Wittig reactions. Analogous derivatives of 5 ~ - a n d r o s t a n e were prepared as synthetic models. In the estrane series the stereochemistry of attachement of the side chain in position 17, biological activity of some compounds, and their chromatographic properties were investigated.
INTRODUCTION Digitalis-type
activity
of
cardenolide
derivatives, in which the butenolide moiety is replaced by
an
acyclic
ester
attached
having
other
generally
steroid features,
STEROIDS 53/1-2
has
been
in
position
required
structural
proven many times (I-4).
January-February 1989 (107-129)
17 to a
In this
107
108
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
context
we may m e n t i o n
21-methoxycarbony]-19-nor-5f3-20-
pregnene-3#,14#-dio], which tory
is
reported
activity
prepared to
acyc]ic
of
side
19-norsteroida]
chain,
inhibi-
of
the
contribution
rings
to
vestigations
of
cardeno]ides
using
the
(I)
with
14#-hydroxy-3-methoxyestrone fusion
same Na+K+-ATPase
(5),
as d i g i t o x i g e n i n e .
The s y n t h e s i s an
have the
by German a u t h o r s
B and C,
type
synthetic
unnatural
8~,gE-
h a s been e l a b o r a t e d
structure-activity this
totally
with
of
relation
as a
(SAR)
cardiotonic-]ike
in-
deriv-
atives. We h a v e c h o s e n (~.~.,
cis)
inhibit
of
8~,9~-fused
because
derivatives pound
the
this
even
some
Na+K+-ATPase
estrane
series
estrane
ske]eton
of
simplest
(6). we
its
As s t a r t i n g used
14~-hydroxy-
3-methoxy-8~,9~-1,3,5(10)-estratrien-17-one ences
6 and 7 ) .
tiary using
hydroxy a
group
mixture
methy]si]y])
The s t e r i c a ] ] y
of
in
y]si]y] crude
ether
acetamide,
II,
the
mixture
and (8-10).
reaction
(TMS) p r o t e c t e d product
alcohol
I
(refer-
hindered was
eno]
ter-
si]y]ated
trimethy]si]y]imidazo]e,
N,N-dimethy]formamide sired
the
(I)
strong]y
com-
bis(tri-
trimethy]ch]orosi]ane In also ether
addition afforded III
by mass s p e c t r a
to the
the
STEROIDS 53/1-2
de-
trimeth-
as p r o v e n which
in
in
the
displayed
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
molecular
ions
Although
of the
sufficiently physical
both
II
and I I I ,
bis-trimethylsilyl
to
stable
methods
or
109
to
derivative
allow
III
was
characterization
undergo it
thin-layer
preparative)
chromatography,
the ketone I I
by traces of acids or even
by
(even
was reconverted i n t o on
prolonged
action of s i l i c a gel, such as in column chromatography. The
IH
NMR
spectrum of I I
exhibits a characteristic
s i n g l e t of t r i m e t h y l s i l y l o x y group singlet
of angular
methyl a t
at
~
=
0.28,
a
8 = 1.06 , a s i n g l e t o f
methoxy group a t ~ = 3.72, and a m u l t i p l e t of
aromatic
protons. W i t t i g reaction o f ketone I I with y l i d e , generated in
situ
from
triphenylmethylphosphonium
sodium s a l t of dimethyl good
yield
converted
the by
sulfoxide
methylene
derivative
hydroboration
17-hydroxymethyl
(10),
derivative
and
iodide
by
afforded
in
IV, which
oxidation
V (11).
into
C17 i n
derivative
Infrared
spectrum
a band
at
drogen
bond
STEROIDS 53/1-2
V I was d e t e r m i n e d of
VI
3 458 cm -1 (12)
in
between
January-February 1989
the
pro-
The c o n f i g u r a t i o n a t by s e v e r a l
tetrachloromethane
confirming
the
The reactioq was
accompanied by p a r t i a l loss o f the t r i m e t h y l s i l y l t e c t i n g group leading t o d i o l VI.
was
methods. exhibits
an i n t r a m o l e c u l a r hydroxy
groups
hyat
C14
110
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
=
J-
=
o ~ cHao~ o ~ s II
III
oH
c_H.~
C)
CH~O
c~o V
IV
IX
~
VI
/cooc~ s
CH~o
~ /
VII
cooc~
C
X Scheme
VIII
XI
XIV
1
STEROIDS 53/1-2
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCIlC SIDE CHAIN
and
C20.
Although
ented Bide chain, of
proves the presence of
the product
17~- and 1 7 ~ - h y d r o x y m e t h y l
ination
with
the
by d e r i v a t i z a t i o n or
this
still
VI w i t h
a ~-ori-
m i g h t be a m i x t u r e
derivatives.
17~-derivative of
111
Such c o n t a m -
was n o t e x c l u d e d even
phenylboric
acid
in ether
with large excess of carbonyldiimidazole in dimeth-
ylformamide because n e i t h e r of
these
the desired d e r i v a t i v e
V I I I in a
V I I or
y i e l d , some unreacted s t a r t i n g Question of the side chain
experiments gave quantitative
alcohol being l e f t .
The
attachment has been f i n a l l y
solved by 1H NMR spectroscopy. The
IH NMR
spectrum
(at
200.059 MHz) e x h i b i t s
several separated groups of proton s i g n a l s I)
which
w e r e assigned
on
experiments. I r r a d i a t i o n of 1.78
the
the
(see
Table
basis o f decoupling C17-H signal
at ~ =
s i m p l i f i e d the m u l t i p l e t o f protons a t C20 to
an
AB system with geminal constant JJJ = 11.0 Hz. The v i c i n a l coupling constants J17,20 = 3.2 and 1.8
Hz
indi-
cate t h a t the hydroxyl group i s oriented towards the Dring,
in agreement with
bridge
between C20-OH
red (IR) spectra. three-proton
the
intramolecular
and C14-0H
The C18 methyl
found by the infraprotons
appear as a
gives no sign
of splitting
even after weighting free induction decay
(FID) by the
STEROIDS 53/1-2
singlet that
hydrogen
Januaw-February1989
112
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
exponential
function,
ral s i g n a l chemical
width shift
substituents
to
of
of
ring
D was
on t h e
the
intensity
ment
at
ring
the of
D indicates
from
singlet
Effect
(NOE),
the
-
8.9~,
depending
from
on
the
the ring
C17-endo-methylene
groups
other
this
because only the
spatial From
C17-CH20H
groups
found
#-cis-arrangement
ring
D in
the
result
analysis The
of
alcohol
chlorochromate
in
VI,
of
V
XII was
(vide
by
pro-
configurations
of
C13-methyl
and
cis is
each
compatible
C14-0H
and
we can d e -
substituents the
to
a NOE e n h a n c e -
whole
been c o n f i r m e d
on t h e synthetic
by s p e c t r o -
infr~).
oxidized
dichloromethane
induced
method of
of
in
the
enhance-
for
all
on
integrated
IR spectrum,
and t h u s
has a l s o ester
the
is
relative
oriented
necessary
diol
( C 2 0 - H a)
the
are
in
the
This
D,
of
S = 3.78
cis-configuration
rive
diol
the
configuration
proximity
the
groups
on t h e
possible
the
configura-
(C18-H)
Overhauser
substituents
scopic
~ = 1.08 at
6.5
our
The r e l a t i v e
changes of
at
of
arrangement
that
signal
As f o l l o w s
series.
the
proton
being
ment.
C18 t o
the
cessing.
with
The s e n s i t i v i t y
and h y d r o x y m e t h y l e n e
determined
irradiation
Hz.
homogeneous.
methyl
of
Nuclear
0.08
protons
configurationally tion
resulting in narrowing the natu-
to
with give
STEROIDS 53/1-2
pyridinium
the
aldehyde
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
Table
113
I
C h a r a c t e r i s t i c IH NMR Data (200 MHz) f o r Diol VI Signal
Assignment
7.04 6.72 6.62 3.78 3.77 3.77 3 47 2 93 2 76 2 63 2 41 1 78 1,30
d dd d dd
s m dd m m m m m
m s
to 2.30 1.08
IX, which was
(J=8)(1H) (J=8 and 2 ) ( 1 H ) (J=2)(1H) (J=11 and 1 . 8 ) ( 1 H ) (3H)
C1-H C2-H C4-H C20-H a OCH3
(IH) (J=11 and 3,2)(IH) (IH) (JAB=I7)(1H) (JAB=I7)(1H)
OH C20-H b Cg-H C6-H a C6-H b
(1H)
(1H) (11H) (3H)
C17-H 3 x C18-H
p u r i f i e d by
filtration
of alumina and then used f u r t h e r
through a column
in the Wittig-Horner
condensation
with methyl
condensation
afforded the TMS-protected
methyl ester XI
(13) in a good y i e l d , s i m i l a r l y as the
analogous reac-
t i o n of the
aldehyde
leading
the e t h y l
to
diethylphosphonoacetate.
The
IX with triethylphosphonoacetate ester
X (13). However, the a t -
tempted cleavage of TMS p r o t e c t i n g group of the 14#-hydroxy group
of XI with a mixture
of zinc
bromide and
t i t a n i u m t e t r a c h l o r i d e (14) was accompanied by e l i m i n a t i o n . The mixture of
STEROIDS 53/1-2
alcohol X I I and
January-February1989
dehydro compound
114
Drasar et ah 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
/coocH.3
/
C.~ac~.3
XIV
cN~
c%o XII
XIII
/
c~o czH~
C.,~iO
h XVI
XV
/
cooc~
H XVII
%
00 OH
O430 XVIII
CH3°
XIX
XX
Scheme 2
STEROIDS 53/I-2
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
115
of the type X I I I obtained was d i f f i c u l t
to separate and
was not f u r t h e r i n v e s t i g a t e d . Therefore, we prepared the alcohol
XII
using
an
analogous sequence in the unprotected 14-hydroxy s e r i e s (15). The d i o l VI was oxidized with chromium t r i o x i d e pyridine
complex in
aldehyde jected
dichloromethane
to
derivative
Wittig-Horner
XII
characterized 370
spectrum
in by
and
corresponding
ester,
to
reaction
giving
a good y i e l d , its
mass
further the
phenolic ether,
matic and
with
the The
alcohol
spectrum
XII
(molecular
characteristic expected
methyl
14~-hydroxy
ions),
structure.
and aromatics.
was ion fully
The
IR
d i s p l a y s , in
S i m i l a r l y , the a d d i t i o n to aro-
e t h y l e n i c protons, s i g n a l s due to
ether, methyl e s t e r , and one angular methyl. o f only
one signal o f
the methyl
astereoisomer side chain. apparent from
with unchanged
(200 MHz; see Table 2).
January-February 1989
methyl
The pres-
pure
di-
1?~-configuration of the
The E-configuration o f the coupling
a
a t C13 ( i . ~ . ,
C18-protons) i n d i c a t e s t h a t the e s t e r X I I i s
STEROIDS 53/1-2
the
e x h i b i t s bands due to an alcohol, unsaturated
200 MHz IH NMR spectrum
ence
give
XIV which, without c h a r a c t e r i z a t i o n , was sub-
diethylphosphonoacetate
m/z
to
the double bond i s
constant 3J20,21 = 15.6 Hz
116
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
Table
2
C h a r a c t e r i s t i c IH NMR Data (200 MHz) f o r Ester X I I
Signal 7 20 7 02 6 71 6 61 5 64 3 77 3 72 2 92 2 80 271 2 42 2.08 to 1,88 0.93
1.40
As
a
dd d dd d dd s s m m m m m m s
model
synthesis, the
Assignment ( J = 1 5 . 6 and 1 0 . 6 ) ( 1 H ) (J=8.3)(1H) ( J = 8 . 3 and 2 . 8 ) ( 1 H ) (J=2.8)(1H) ( J = 1 5 . 6 and 0 . 5 ) ( 1 H ) (3H) (3H) (1H) (1H) (1H) (2H) (3H)
C20-H Cl-H C2-H C4-H C21-H -COOCH 3 -OCH 3 C9-H C6-H a C6-H b
(3H)
3 x C18-H
reaction
we a l s o
for
elaborated
14#-trimethylsilyloxy
and X I
to
the
Lewis acids. character group
free It
of
the
alcohols
protected
room
checked
temperature with
by
compounds
1 II,
-
the
in
4 h. V,
II,
V,
mineral
or
according
These
and X I
to
the
trimethylsily]
treatment
tetrachloride for
with
~queous hydrochloric or
deblocking
derivatives
that,
alcohol,
dichloromethane-methanol
at
in
by r e a c t i o n
h a s been f o u n d
and t i t a n i u m
above-described
a method for
group
c a n be r e m o v e d w i t h
bromide
the
acid with
in zinc
dichloromethane reactions and f o u n d
STEROIDS 53/1-2
were to
be
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
preparatively
usable with
all
these cases,
to
minor
tography Of t h e
longer
side-products [TLC]),
reagents
(detected
by t h i n - l a y e r - c h r o m a -
separable tin
with
Table
3
this
series
acids
by
rise
chromatography.
tetrachloride
in dichloro-
The e x p e r i m e n t a l are given
gave
In
with
methane was n o t s u i t a b l e . tained
two compounds.
treatment
easily tried,
the former
117
results
ob-
i n T a b l e 3.
Cleavage of 1 4 ~ - T r i m e t h y l s i l y l o x y D e r i v a t i v e s
Starting compound II a IIb II c IId
IIe V a XI d
Reagent
Medium
Reaction time, h
ZnBr2 CH2Cl2 HCl CH2CI2-CH30H TiCl 4 CH2Cl2 ZnBr2+ T i C l 4 CH2Cl 2 SnC14 CH2C12 ZnBr 2 CH2C12 ZnBr2+ TiC14 CH2C12
4 4 4
Product
Yield
I I
71% 76%
I
64~
I
68~
4 1 1
decomposition 56% VI
1.5
decomposition
a S t a r t i n g compound (20 mg) was dissolved in d i c h l o r o methane (1 mL), and anhydrous zinc bromide (25 mg) was added to the s o l u t i o n . A f t e r the r e a c t i o n , the mixture was p a r t i t i o n e d between ether and potassium hydrogen carbonate s o l u t i o n , and the ethereal e x t r a c t s were d r i e d , evaporated, and chromatographed on s i l i c a gel. b Methanol (0.4 mL) and 37% aqueous h y d r o c h l o r i c acid (0.1) were added to a s o l u t i o n o f the s t a r t i n g compound (20 mg) in dichloromethane ( I mL) and the reaction mixture was processed as described in footnote a, c Same procedure a, 25 mg o f t i t a n i u m t e t r a c h l o r i d e . d Same procedure a, 25 mg of 1:1 mixture. e Same procedure a, 25 mg o f t i n t e t r a c h l o r i d e .
STEROIDS 53/1-2
January-February1989
I~8
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
As a second model Hornet
reaction,
reaction of the
formyl-5~-androstane acetate and methyl
we studied the Wittig-
chemically (XV)
very
with
simple
17/3-
triethylphosphono-
diethylphosphonoacetate,
leading
to
esters XVI and XVll. In all aldehydes
cases,
the
IX, XIV,
homogeneous
studied
and
products
XV of
double bond as evidenced
condensations
afforded
stereochemically
E-configuration
at the 20,21
by the high coupling
of the C20-H and C21-H protons
of the
constant
(16 Hz).
For evaluating the s y n t h e t i c reactions, as well as f o r checking p u r i t y of the products, we i s o c r a t i c reverse-phase
an
high pressure l i q u i d chromato-
graphy (HPLC) method, using
methanol-water (9:1; v / v )
as the mobile phase. The chromatographic Table 4) also includes
elaborated
analysis
compounds present
t i o n mixtures in the synthesis of
ketone
(see
in the reacI
from
diketone X V I I I , the unsaturated hydroxyketone
the
XIX, and
the bisdehydro d e r i v a t i v e XX. Since
the
key
compound X I I
compound,
was s y n t h e s i z e d
we t e s t e d
the
as a
potentially
active
inhibitory
a c t i v i t y (see references 16 and 17) of t h i s
STEROIDS 53/1-2
Na+K+-ATPase
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
Table
119
4
Separation of Reverse-Phase
Synthetic Estrane Derivatives by HPLC i n M e t h a n o l - W a t e r 9 : 1 ( v / v )
Compound
I II IV
Capacity f a c t o r k'
Retention time t R (min) 3.57 9.33 37.50 11.88 5,17 10.55 8.96 5,67 3.83 3,33 5.67
V
VI X XI XII XVIII XIX XX
0.53 3.00 15.09 4.10 1.22 3,53 2.85 1.43 0.64 0.43 1.43
Apparatus: Milton Roy/LDC system Support Unit I pump, s t a i n l e s s steel column (250 x 4 mm i . d . ) packed with SEPARON Si C18 (10 jum), UV-detector UVM-4 (Developmental Workshops o f the Czechoslovak Academy o f Sciences), and a K n a u e r No. 36.00.00 loop valve. Samples were applied in dichloromethane (10juL) and eluted with methanol-water (9:1 v/v) at 25°C, flow rate I mL/min, pressure 4.82 MPa (685 p . s . i . ) , d e t e c t i o n at 254 rim.
compound
and o f
compound Vl
(Table
only very low i n h i b i t o r y a c t i v i t y ,
5).
We h a v e f o u n d
comparable with t h a t
of 3 , 1 4 , 1 7 - t r i o l s derived from analogous skeletons (6). However,
an
evaluation
of
r e l a t i o n s h i p s f o r such new types of
STEROIDS 53/1-2
January-February 1989
structure-activity xenobiotics
based
120
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
on s y n t h e t i c
will
steroid
skeletons
of unnatural
ring f u s i o n
require more experimental m a t e r i a l . This
study describes a new method of construction
of the side chain in cardenolide analogues in which the butenolide r i n g i s replaced unsaturated steroid
ester
skeleton
However,
the
alcohol X I I ,
grouping with
target exhibits
an
by on
a
similar
of
low
conjugated
synthetic
unsaturated
compound only
a
racemic
8~,9~-fusion.
the synthesis, the inhibitory
activity
towards Na+K+-ATPase (see Table 5).
Table
5
I n h i b i t i o n of Na+K+-ATPase by Xenobiotics VI and X I I Molar [mol.L - I ] concentration 10 - 4 3.10 -5 10 - 5 3.10 -6
I n h i b i t i o n by VI
I n h i b i t i o n by X I I
6% 1% _
Conditions as described in Na+K+-ATPase used (EC3.6.t.3)
25% 11% 4% _ references 16 and 17, w a s from pig k i d n e y (16).
EXPERIMENTAL The melting block (VEB A n a l y t i k , corded on a UR-20
points were determined on a Boetius Dresden, GDR). IR spectra were re( Zeiss, Jena, GDR) spectrometer,
STEROIDS 53/I-2
January-February 1989
Drasar et ah 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
121
wavenumbers are given in cm- I . IH NMR spectra were measured on a BS-468 (60 MHz, Tesla Brno CSSR) and Varian XL-200 (200 MHz, Palo A l t o USA) instrument in d e u t e r i o chloroform with t e t r a m e t h y l s i l a n e as i n t e r n a l standard, chemical shifts are given in the ~-scale (ppm), coupling constants (J) and signal widths (W) in Hz. A l l the s p e c t r a l parameters w e r e obtained by the f i r s t order analysis. Mass s p e c t r a were o b t a i n e d w i t h an AEI-901 i n s t r u m e n t , u n l e s s s t a t e d o t h e r w i s e . Preparative
chromatography
was
performed
on
columns o f s i l i c a g e l a c c o r d i n g t o P i t r a (60 - 120 ~um, Service Laboratories of the Institute of Organic Chemistry and Biochemistry, Praha); t h i n - l a y e r chromatography was c a r r i e d out on s i l i c a gel G according t o S t a h l (Woelm) o r on S i l u f o l UV-254 p l a t e s (Kavalier, C z e c h o s l o v a k i a ) ; d e t e c t i o n by s p r a y i n g with 96~ sulfuric acid and heating or by UV l i g h t ( C h r o m a t o l i t e ) . Solutions w e r e dried over anhydrous magnesium s u l f a t e , and solvents w e r e removed on a r o t a t o r y e v a p o r a t o r a t 40 - 50 °C and 2 2.5 kPa. Analytical s a m p l e s were d r i e d o v e r p h o s p h o r u s p e n t o x i d e a t a b o u t 25 Pa. rac-3-Methoxy-14B-trimethvlsilyloxv-8~.g~-estra-l.3.5(lO)-%rien-17-one ( I I ) T r i m e t h y l s i l y l i m i d a z o l e(6 mL; 41 mmol), b i s ( t r i m e t h y l silyl)acetamide (6 mL; 24 mmol) and t r i m e t h y l c h l o r o s i l a n e (4 mL; 32 mmol) were added t o a s o l u t i o n of hydroxyketone I (2 g; 6.6 mmol) in N,N-dimethylformamide (20 mL). The mixture was s t i r r e d a t 65°C f o r 7 h, water (100 mL) was added, and the mixture was extracted w i t h ether (3 x 50 mL). The combined ethereal e x t r a c t s were dried and taken down, the residue was applied onto a column of s i l i c a gel (100 g) and, a f t e r standing f o r I h, chromatographed in benzene-light petroleum ( 1 : 1 ) . The m a i n f r a c t i o n was evaporated, and the o i l y residue was mixed with l i g h t petroleum, the separated c r y s t a l s were f i l t e r e d and washed with l i g h t petroleum, y i e l d 1.96 g (83%) o f t r i m e t h y l s i l y l ether I I , m.p. 147 t o 150 °C. Mass spectrum (m/z): 372 (M+), 282 (M H O S i ( C H 3 ) 3 ) . I H NMR s p e c t r u m ( d e u t e r i o c h l o r o f o r m , extern a l l o c k ) : 0 . 2 8 s (9H, ( C H 3 ) 3 S i O - ) , 1.06 s (3H, a n g u l a r methyl), 3 . 7 2 s (3H, CH30- ) , 6.61 to 7.09 m (3H, aromatic protons). For C22H3203Si (372.6) calculated: 70.92~ C, 8 . 6 6 ~ H; f o u n d : 71.23~ C, 8.84% H.
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rac-17-Methylene-8~.9~-estra-1.3,5(10)-triene3 . 1 4 B - d i o l 3-Methyl Ether 1 4 - T r i m e t h y l s i l y l e t h e r ( I V ) Sodium h y d r i d e ( 4 8 1 mg; o f 50% suspension i n mineral o i l ; 10 mmol) was washed w i t h l i g h t petroleum (3 x 20 mL) under argon, mixed w i t h d i m e t h y l s u l f o x i d e (37 mL), and heated to 65°C for 1 h under argon. Triphenylmethylphosphonium iodide ( 3 . 3 7 g; 8 . 3 4 mmol) was added a t room temperature, the m i x t u r e was s t i r r e d f o r 30 min~and the p r o t e c t e d ketone I I (732 mg; 2 mmol) was added. After stirring at 65°C for 20 h, the r e a c t i o n m i x t u r e was p a r t i t i o n e d between s a t u r a t e d ammonium c h l o r i d e s o l u t i o n and e t h e r . The aqueous phase was e x t r a c t e d w i t h e t h e r , the combined e t h e r e a l e x t r a c t s were d r i e d , concentrated i_Qn vacuo, and chromatographed on a column o f s i l i c a gel (100 g) i n l i g h t petroleum. The main f r a c t i o n afforded 501 mg (69%) o f ether IV, m.p. 75 t o 77°C. Mass spectrum : ( m / z ) : 370 ( M + ) , 280 (M - H O S i ( C H 3 ) 3 ) . 1H NMR s p e c t r u m (deuteriochloroform): 0 . 9 4 s (3H, a n g u l a r m e t h y l ) , 3.60 s (3H, C H 3 0 - ) , 4 . 6 3 m (2H, C=CH2, W = 1 0 ) , 6 . 4 7 t o 7 . 0 5 m (3H, a r o m a t i c p r o t o n s ) . F o r C23H3402Si ( 3 7 0 . 6 ) c a l c ulated: 74.54% C, 9.29% H; found: 74.63% C, 9.29% H. rac-17B-Hydroxvmethy1-8E,9~-estra-1,3,5(10)-tri@q~$ . 1 4 B - d i o l 3-Methyl Ether 1 4 - T r i m e t h v l s i l y l Ether (V) L i t h i u m aluminium h y d r i d e (100 mg; 2.6 mmol) i n ether (4 mL) was added a t -15°C t o a s o l u t i o n o f methylene d e r i v a t i v e IV (100 mg; 0.27 mmol) and boron t r i f l u o r i d e e t h e r a t e ( 0 . 5 mL; 0.41 mmol) i n e t h e r (3 mL). The m i x t u r e was s t i r r e d a t -15°C f o r 1.5 h and then a t room temperature f o r 30 min, decomposed w i t h s a t u r a t e d sodium s u l f a t e s o l u t i o n (5 mL) and water (10 mL) and the aqueous phase was e x t r a c t e d w i t h e t h e r . The ethereal extracts were dried, the solvent was evaporated, and the residue was dissolved in t e t r a h y d r o f u r a n (3 mL). A q u e o u s potassium h y d r o x i d e (10%; 2.5 mL) and hydrogen peroxide (30% aqueous solution; 1 . 5 mL) w e r e added a t O°C. After stirring at O°C f o r 30 m i n , t h e m i x t u r e was d i l u t e d with water and extracted with ether. The e x t r a c t was d r i e d and t a k e n down, and t h e r e s i d u e was a p p l i e d onto a silica gel column (100 g ) , and e l u t e d s u c c e s s i v e l y with benzene, benzene-ether (9:1), and b e n z e n e - e t h e r (1:1). The main fraction a f f o r d e d 44 mg (46%) o f s i l y l d e r i v a t i v e V;
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further fractions gave d i o l V I . Compound V was o b t a i n e d as a g l a s s y substance. Mass s p e c t r u m (m/z): 388 (M+), 298 (M - H O S i ( C H 3 ) 3 ) , 370 (M - H20), 262 (298 CH3OH). IR s p e c t r u m (chloroform): 3630 (OH), 2845, 1262, 1252) (CH3~-)'IHN 1611, 1582, 1502 ( a r o m a t i c r i n g ) , 842 (Si-C . MR spectrum, (tetrachloromethane, external lock): 0.10 s (9H, ( C H 3 ) 3 S i O - ) , 0 . 9 9 s (3H, angular methyl), 3.4 to 4.0 m (2H, -CH2OH), 3 . 7 3 s (3H, C H 3 0 - ) , 6 . 5 0 t o 7 . 1 0 m (3H, a r o m a t i c p r o t o n s ) . For C23H3603Si (388.6) calculated: 71.08~ C, 9.34~ H; f o u n d : 71.27~ C, 9.56~ H. rac-17B-Hvdroxymethyl-8~.9~-estra-1.3.5(10)-triene3,14~-di01 3-Methyl Ether (VI) Further fraction in the chromatography of alcohol V afforded diol Vl as a g l a s s y m a t e r i a l i n t h e y i e l d o f 34 mg ( 4 0 ~ ) . Mass s p e c t r u m (m/z): 298 (M H20), IR s p e c t r u m (tetrachloromethane): 2845, 1270, 1243 ( C H 3 0 - ) , 1611, 1582, 1504 (aromatic ring), 3642, 3601 (OH), 3458 ( h y d r o g e n b o n d ) . 1H NMR s p e c t r u m ( d e u t e r i o chloroform, external lock): 0.96 s (3H, angular methyl), 3.30 to 4.10 m (2H, -CH2OH), 3.73 s (3H, CH30-), 6.50 to 7.10 m (3H, aromatic protons). For C20H2803 (316.4) calculated: 75.91% C, 8.92% H; f o u n d : 75.67~ C, 9.28% H. rac-(20E)-21-Methoxycarbonyl-19-nor-8~.9~-oreana1,~,~(10).20-tetraene-3.14B-diol 3-Methyl Ether 14-Trimethylsilyl Ether (XI) Alcohol V (270 mg; 0.69 mmol) was d i s s o l v e d in dichloromethane (5 mL), and p y r i d i n i u m c h l o r o c h r o m a t e (300 mg) was added. The m i x t u r e was s t i r r e d at room temperature for 1 h and f i l t e r e d t h r o u g h a column o f a l u m i n a (30 g; R e a n a l , activity II), which was t h e n washed w i t h benzene. The f i l t r a t e was e v a p o r a t e d and the residue (containing aldehyde IX) dissolved in 1 , 2 - d i m e t h o x y e t h a n e (10 mL). Sodium h y d r i d e (168 mg o f 50% s u s p e n s i o n i n m i n e r a l o i l ) was washed w i t h light petroleum (3 x 25 mL) under a r g o n , and l a y e r e d w i t h 1 , 2 - d i m e t h o x y e t h a n e ( 1 7 . 5 mL). M e t h y l d i e t h y l p h o s p h o n o a c e t a t e ( 0 . 6 5 mL; 3 . 5 mmol) was added to the stirred mixture at room t e m p e r a t u r e under argon and t h e stirring was c o n t i n u e d for further 20 m i n . The above-described solution of aldehyde IX in 1 , 2 - d i m e t h o x y e t h a n e was t h e n added, and t h e m i x t u r e was stirred
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room temperature
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2 h under
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Water
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Drasar et ah 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
was added (5 mL) and t h e v o l a t i l e
organic
solvents
were
distilled off i__on vacuo. The r e s i d u e was mixed w i t h e t h e r (50 mL) and washed w i t h water (3 x 20 mL). After d r y i n g and e v a p o r a t i o n o f the s o l v e n t , the residue was chromatographed on a column o f s i l i c a gel (50 g) i n light petroleum-benzene ( 3 : 2 , 250 mL) and then in benzene (300 mL). The main f r a c t i o n gave 290 mg (95%) o f compound Xl as a glassy substance. M a s s spectrum
(m/z): 442 (M+), 352 (M H O S i ( C H 3 ) 3 ) , 240 (352 C6H802), 159 (CH3OCIoH9), 157 (CH3OCIoH7). IR s p e c t r u m (tetrachloromethane): 1651, 1724 (-COOCH3), 1500, 1610 (aromatic ring), 840 ( S i ( C H 3 ) 3 ) . 1H NMR s p e c t r u m ( t e t rachloromethane, external l o c k ) : 0 . 0 5 s (9H, S i ( C H 3 ) 3 ) , 0 . 7 8 s (3H, a n g u l a r m e t h y l ) , 3 . 5 4 s (3H, -COOCH3), 3 . 5 0 s (3H, -OCH3), 5 . 5 8 bd (1H, C21-H, J = 1 6 ) , 6 . 2 0 t o 7.15 m (4H, aromatic protons + C20-H). For C20H3804Si (442.7) calculated: 70.55% C, 8.65% H; f o u n d : 70.84% C, 8.90% H. rac-(20E)-21-Ethoxvcarbonyl-19-nor-8~.9E-oreQna1.3.5(10).20-tetraene-3,14~-diol 3-Methyl Ether 14-Trimethylsilyl Ether (X) The t i t l e compound was p r e p a r e d as d e s c r i b e d f o r t h e methyl ester XI, using triethylphosphonoacetate instead of methyl diethylphosphonoacetate in the same m o l a r r a t i o . Compound X was o b t a i n e d as a glassy substance i n 87% y i e l d , m a s s spectrum (m/z): 456 (M+), 366 (M -
(CH3)3SiOH), 321. 1H NMR s p e c t r u m (tetrachloromethane e x t e r n a l lock): 0 . 0 5 s (9H, O S i ( C H 3 ) 3 ) , 0 . 8 4 s (3H, angular methyl), 1.13 t (3H, -OCH2CH3, J = 7 . 5 ) , 3.57 s (3H, CH30- ), 3.99 q (2H, -OCH2CH3, J=7.5), 5.60 bd ( I H , C21-H, J20,21=16), 6.20 t o 7.00 (4H, aromatic protons + C20-H). For C27H4004Si (456.7) calc u l a t e d : 71.00% C, 8.83% H; found: 71.23% C, 8.91% H.
rac-(20E)-21-Methoxvcarbonvl-19-nor-8E. 9~-orean~1.3.5(10).20-tetraene-3.14B-diol 3-Methyl Ether (XII) P y r i d i n e ( 0 . 8 7 mL; 10.7 mmol) was added u n d e r stirring and c o o l i n g w i t h ice to a suspension o f chromium t r i o x i d e (540 mg; 5.40 mmol) and anhydrous magnesium sulfate (450 mg) in dichloromethane (20 mL). After s t i r r i n g a t O°C f o r 20 min, d i o l VI (200 mg, 0.55 mmol) i n dichloromethane (10 mL) was added t o the m i x t u r e . The m i x t u r e was s t i r r e d a t 0 °C f o r 30 min and a t room
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temperature f o r 30 min, filtered through an alumina column (30 g; Reanal, a c t i v i t y I I ) , which was washed w i t h ether-benzene ( 2 : 1 ) , and the f i l t r a t e s , c o n t a i n i n g the aldehyde XIV, were taken down. Sodium hydride (154 mg, of 50% suspension in mineral o i l , 3.2 m m o l ) was washed w i t h l i g h t petroleum (3 x 20 mL) under argon and mixed with 1,2mdimethoxyethane ( 3.5 mL ) and methyl diethylphosphonoacetate (0.6 mL; 3.35 mmol). A f t e r s t i r r i n g a t room temperature f o r 10 min, aldehyde XIV (220 mg) in 1,2-dimethoxyethane (4 mL) was added, the m i x t u r e was s t i r r e d a t room temperature f o r 7 h and p a r t i t i o n e d between water (100 mL) and e t h e r (50 mL). The aqueous phase was e x t r a c t e d w i t h e t h e r (3 x 40 mL), and the combined e t h e r e a l e x t r a c t s were d r i e d and evaporated. C r y s t a l l i z a t i o n from e t h e r - l i g h t petroleum gave 140 mg (68% from the s t a r t i n g VI) o f e s t e r X I I , m.p. 153 - 157°C. Mass spectrum (m/z): 370 (M+), 339 (M CH30- ), 352 (M H20 ), 240 (352 H2C=CH-CH=CH-COOCH3), 225 (240 - CH3- ). IR s p e c t r u m (chloroform): 3610 (OH), 1713, 1652, 1162 (C=C-COOCH3), 2845, 1267, 1242 ( C H 3 0 - ) , 1642, 1588, 1505 ( a r o m a t i c ring). IH NMR spectrum ( d e u t e r i o c h l o r o f o r m ) : 0.91 s (3H, angular m e t h y l ) , 3.74 s (3H, CH30-), 3.70 s (3H, COOCH3), 5 . 6 2 d (1H, C21-H, J = 16), 6.50 to 7.45 m (4H, a r o m a t i c p r o t o n s + C20-H). For C23H3004 ( 3 7 0 . 5 ) calculated: 74.56% C, 8.16%H; f o u n d : 74.70~ C, 8.36% H. (20E)-21-Ethoxvcarbonvl-5~-pregn-20-ene (XVI) Sodium h y d r i d e (415 mg o f 50% s u s p e n s i o n i n m i n e r a l oil; 86 mmol) was washed w i t h l i g h t p e t r o l e u m (3 x 10 mL) under a r g o n , mixed w i t h 1 , 2 - d i m e t h o x y e t h a n e (10 mL~ and t h e n with triethylphosphonoacetate ( 1 . 7 1 mL; 8 . 6 mmol). The m i x t u r e was s t i r r e d a t room t e m p e r a t u r e f o r 20 min and a l d e h y d e XV ( r e f e r e n c e 18, 500 mg; 174 mmol) in 1,2-dimethoxyethane (5 mL) was added d r o p w i s e . The r e a c t i o n m i x t u r e was s t i r r e d a t room temperature f o r 12 h, t a k e n down j n v a c u o , a n d t h e r e s i d u e was p a r t i t i o n e d between water (50 mL) and e t h e r (50 mL). The aqueous phase was e x t r a c t e d w i t h e t h e r (3 x 30 mL) and the combined ethereal extracts were dried, evaporated, d i s s o l v e d i n benzene, and f i l t e r e d t h r o u g h a column of silica g e l (50 g ) , w h i c h was t h e n washed w i t h benzene. Evaporation of the filtrate afforded ester XVI as an amorphous solid (474 mg; 76%). IR spectrum (chloroform): 1721, 1651, 1184 (C=C-COOR). 1H NMR s p e c -
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trum ( d e u t e r i o c h l o r o f o r m ) : 6.93 dd (IH, C20-H, J20,17 = 7.5, J20,21 = 16), 5.75 d (1H, C21-H, J20,21 = 16), 4.20 q (2H, OCH2CH3, J = 7 ) , 1.31 t (3H, OCH2CH3, J = 7), 0.71 and 0 . 6 5 2 s (2 x 3H, a n g u l a r m e t h y l s ) . For C24H3802 (358.6) calculated: 80.39~ C, 1 0 . 6 8 ~ H; f o u n d : 8 0 . 6 6 ~ C, 1 0 . 7 1 ~ H.
(20E)-21-Methoxycarbonvl-5~-Dregn-20-ene (XVII) The compound was prepared as described above f o r e s t e r XVI using methyl d i e t h y l p h o s p h o n o a c e t a t e (1.6 mL; 8.6 mmol) i n s t e a d o f t r i e t h y l p h o s p h o n o a c e t a t e . The same i s o l a t i o n gave the g l a s s y e s t e r XVII as an o i l (436 mg; 74~). IR spectrum ( c h l o r o f o r m ) : 1722, 1651, t439 (C=C-COOR). 1H NMR s p e c t r u m ( d e u t e r i o c h l o r o f o r m ) : 6.98 dd (1H, C20-H, J 1 7 , 2 0 = 7 . 5 , J 2 0 , 2 1 = 1 6 ) , 5 . 7 4 d (1H, C21 - H ' J 2 0 , 2 1 = 1 6 ) , 3 . 7 0 s (3H, CH30CO), 0 . 6 4 and 0 . 8 0 2 x s (2 x 3H, a n g u l a r m e t h y l s ) . For C23H3602 (344.5) calculated: 80.18~ C, 10.53~ H; found: 80.39~ C, 10.76~ H. N~Glear Overhauser E f f e c t (NOE) Exoeriment w i t h D i o l VI a t 200 MHz Before the measurement oxygen was t h o r o u g h l y driven o f f by i n t r o d u c i n g argon into solution of the diol in CDC13 t o p r e v e n t s p i n r e l a x a t i o n . Changes o f i n t e g r a t e d intensities of the singlet at S = 1 . 0 8 on i r r a d i a t i o n of the proton signal at ~ = 3.78 were followed. Free induction d e c a y ( F I D ) f o r t h e n o r m a l s p e c t r u m was s u b tracted f r o m FID f o r t h e s p e c t r u m o b t a i n e d by d e c o u p l ing of the proton a t ~ = 3 . 7 8 so as t o e l i m i n a t e the internal standard (tetramethylsilane) signal. The difference spectrum obtained by t r a n s f o r m a t i o n of the resulting FID gave a p o s i t i v e s i g n a l a t ~ = 1 . 0 8 . The relative NOE e n h a n c e m e n t v a l u e amounted t o 6 . 5 - 8.9% relative to the tetramethylsilane reference signal.
ACKNOWLEDGMENTS The
authors
are
indebted
to
Miss.
H.
Kapi~kov&
for
measurement o f the IR s p e c t r a and t o Dr. I J. Smol~kov~ l f o r t h e i r i n t e r p r e t a t i o n , t o Mrs. J. J e l l n k o v a and Dr. D. ~aman f o r the 60 MHz IH NMR s p e c t r a , t o Dr. A. Trka for mass spectral measurements, and t o the s t a f f o f the A n a l y t i c a l Laboratory headed by Dr. J. Hor&~ek f o r the elemental analyses. A l l of t h e m are from the
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Prague I n s t i t u t e o f O r g a n i c C h e m i s t r y and B i o c h e m i s t r y . T h e i r t h a n k s a r e a l s o due t o K.N. Dzhandzhugazyan o f M. M. Shemyakin Institute of Bio-organic Chemistry, Moscow, f o r measurements o f Na+K+-ATPase i n h i b i t i o n . NOTES A part o f t h i s work has been p u b l i s h e d i n a p r e liminary form (19). P a r t CCCXXXV i n the series On S t e r o i d s , Part CCCXXXIV see ( 2 0 ) . REFERENCES 1. 2. 3.
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B o u t a g y JS and Thomas RE ( 1 9 7 1 ) . C a r d e n o l i d e a n a logues I. Route f o r p r e p a r i n g s e m i s y n t h e t i c analogues of digitoxigenin. AUST J CHEM 2 4 : 2 7 2 3 - 2 7 2 8 . Thomas R, B o u t a g y J, and G e l b a r t A ( 1 9 7 4 ) . S y n t h e s i s and b i o l o g i c a l activity of semisynthetic digitalis a n a l o g s . J PHARM SCI 6 3 : 1 6 4 9 - 1 6 8 3 . T h e i l F, L i n d i g C, and Repke K ( 1 9 8 0 ) . Partial syntheses of cardenolides and c a r d e n o l i d e a n a logues III. Synthesis of cardenolide-analogous methyl ~-steroidyl-crotonates. J PRAKT CHEM 322: 1012-1020. G u n t e r t TW, and L i n d e HHA ( 1 9 8 1 ) . Chemistry and structure-activity relationships of cardioactive steroids. I n : Handbook o f ExPerimental Pharmacology, Springer-Verlag, Berlin (1981), vol 56/I, pp 1 3 - 2 4 . P o n s o l d K, and Wunderwald M ( 1 9 8 3 ) . A synthetic approach to cardiotonic 19-nor steroids. In: lOth Conference on Isoorenoids, Abstracts of papers, T r e b o n , CSSR, O c t o b e r 16-21, pp 7 4 - 7 5 . Platonova AV, Lailiev AO, Ananchenko SN, and T o r g o v IV ( 1 9 8 2 ) . A study on s t e r e o c h e m i s t r y o f 8 ( 9 ) - d o u b l e bond r e d u c t i o n i n 1 7 - k e t o - and 1 7 ~ - h y droxy derivatives of 14~-hydroxy estratetraene. Synthesis of steroids with potential cardiotonic activity. BIOORG CHEM 8 : 5 4 2 - 5 4 9 . Z a k h a r y c h e v AV, Hora I , A b o u M u s t a f a E, Ananchenko SN, and T o r g o v IV ( 1 9 7 0 ) . 1 4 - H y d r o x y s t e r o i d s Pt 5. 3- methoxy - ~ ' 3 ' 5 ( 1 0 ) ' 9 ( 1 1 ) - 8 , 1 4 Cyclization of
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16.
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
secoestratetraenedione-14,17. IZV AKAD NAUK SSSR, SER KHIM 1 9 7 0 : 1 3 5 1 - 1 3 5 6 . P i e r c e Chemical Co. S y l i l a t i n g reagents, formulati o n s , and methods; and p a p e r s c i t e d t h e r e i n . In: Handbook ~n~ G e n e r a l C a t a l o Q , Pierce Eurochemie ( 1 9 8 7 ) , pp 184-196. A l s t o n KT, B e b b i n g t o n PM, Green SE, Morgan ED, and P o o l e CF ( 1 9 7 6 ) . The s y n t h e s i s o f some c h o l e s t - 7 en-6-one derivatives related to ecdysones. STEROIDS 2 7 : 6 0 9 - 6 1 6 . Egorova VV, K r y u t c h e n k o EC, Ananchenko SN, Pouzar V, Ora~ar P, and Havel M ( 1 9 8 1 ) . 3-Methoxy-17-methylen-14~crimethylsilyloxy-8~,9~-1,3,5(10)-estratriene and method of its preparation. CZECH P a t e n t No 219765. Egorova VV, K r y u t c h e n k o EG, Ananchenko SN, Pouzar V, D r a ~ a r P, and Havel M ( 1 9 8 1 ) . 17~-Hydroxymethyl-3-methoxy-14#-trimethylsilyloxy-8~,9~-1,3,5(10) estratriene and method o f i t s preparation. CZECH P a t e n t No 225014 [CHEM ABSTR 1 0 5 : 6 0 8 1 0 k ] . Tich~ M. The d e t e r m i n a t i o n of intramolecular hydrogen b o n d i n g by i n f r a r e d s p e c t r o s c o p y and i t s application in stereochemistry. In: Advances in Organic C h e m i s t r y (Raphael RA, Taylor EC, and Wynberg H, e d s ) , I n t e r s c i e n c e P u b l i s h e r s , New York ( 1 9 6 5 ) , v o l 5, pp 115-298. Dra~ar P, Pouzar V, Havel M, Egorova VV, and Ananchenko SN ( 1 9 8 1 ) . (20E)-3-Methoxy-21-alkoxycarbonyl-19-nor-14#-trimethylsilyloxy-8~,9~,17~-l3,5(lO),20-pregnatetraene and method o f i t s p r e p a r a t i o n . CZECH P a t e n t No 225013 [ C H E M ABSTR 105: 60821q]. Dra~ar P, Pouzar V, Havel M, Egorova VV, and Ananchenko SN ( 1 9 8 1 ) . Method o f p r e p a r a t i o n o f t h e free 14-hydroxyestrane derivatives. CZECH P a t e n t No 225023 [CHEM ABSTR 105:60811m]. Dra~ar P, Pouzar V, Have1 M, Egorova VV, and Ananchenko SN ( 1 9 8 1 ) . (20E)-3-Methoxy-21-methoxycarbonyl-19-nor-14#-hydroxy-8~,9~,17~ -1,3,5(10),20-pregnatetraen and method of its preparation. CZECH P a t e n t No 221616 [CHEM ABSTR 1 0 5 : 9 7 8 0 4 n ] . Dzhandzhugazyan KN, Modyanova NN, and O v c h i n n i k o v YuA ( 1 9 8 1 ) . Na+K+ A c t i v a t e d a d e n o s i n e t r i p h o s p h a tase from pig kidney, I, Isolation and chemical characterization of BIOORG KHIM 7 : 8 4 7 - 8 5 7 .
enzyme and
its
STEROIDS 53/I-2
subunits.
January-February1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
17.
18.
19.
20.
129
Mirsalikhova NM, Umarova ST, P a l y a n c NSh, and Abubakirov NK ( 1 9 7 6 ) . Inhibition of transport Na+K + ATP-ase by c a r d e n o l i d e s f r o m s t r o p h a n t h i d i n e group and t h e study of structure activity relationships. KHIM PRIR 80EDIN (TASHK) 1976: 188-194. Pouzar V and Havel M ( 1 9 8 1 ) . P r e p a r a t i o n and a b s o lute configuration at C20 o f 2 1 - n o r - 5 ~ - c h o l a n 24-->20-olide derivatives. COLLECT CZECH CHEM COMMUN 4 6 : 1 0 7 - 1 1 7 . Egorova VV and D r a ~ a r P ( 1 9 8 1 ) . The s y n t h e s i s o f 17-CH2X-derivatives of some B/C-isomeric-3-methoxy-14~-hydroxyestratrienes. In: Symoosium on S t e r o i ~ C h e m i s t r y and B i o c h e m i s t r y , Attila Joszef University, Szeged, H u n g a r y , May 2 7 - 3 0 . S h o r t comm u n i c a t i o n No 18. Pouzar V, K ~ r ~ s z o v ~ L, and Havel M ( 1 9 8 7 ) . Prepar a t i o n o f 21-methoxycarbonyl-21-methylene-5-pregnen-3#-ol derivatives. COLLECT CZECH CHEM COMMUN 52:2738-2744.
STEROIDS 53/I-2
January-February1989
ABSTRACT Racemic 14#-hydroxy-3-methoxy-8~,9~-1,3,5(10)-estratriene-17-one (I), obtained by t o t a l synthesis, was c o n v e r t e d i n t o a d e r i v a t i v e with alkoxycarbonylethylenic side chain, rac-(20E)-21-methoxycarbonyl-19nor-8~,9~-pregna-1,3,5(10),20-tetraene-3,14~-diol 3-methyl ether (XII) using two Wittig reactions. Analogous derivatives of 5 ~ - a n d r o s t a n e were prepared as synthetic models. In the estrane series the stereochemistry of attachement of the side chain in position 17, biological activity of some compounds, and their chromatographic properties were investigated.
INTRODUCTION Digitalis-type
activity
of
cardenolide
derivatives, in which the butenolide moiety is replaced by
an
acyclic
ester
attached
having
other
generally
steroid features,
STEROIDS 53/1-2
has
been
in
position
required
structural
proven many times (I-4).
January-February 1989 (107-129)
17 to a
In this
107
108
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
context
we may m e n t i o n
21-methoxycarbony]-19-nor-5f3-20-
pregnene-3#,14#-dio], which tory
is
reported
activity
prepared to
acyc]ic
of
side
19-norsteroida]
chain,
inhibi-
of
the
contribution
rings
to
vestigations
of
cardeno]ides
using
the
(I)
with
14#-hydroxy-3-methoxyestrone fusion
same Na+K+-ATPase
(5),
as d i g i t o x i g e n i n e .
The s y n t h e s i s an
have the
by German a u t h o r s
B and C,
type
synthetic
unnatural
8~,gE-
h a s been e l a b o r a t e d
structure-activity this
totally
with
of
relation
as a
(SAR)
cardiotonic-]ike
in-
deriv-
atives. We h a v e c h o s e n (~.~.,
cis)
inhibit
of
8~,9~-fused
because
derivatives pound
the
this
even
some
Na+K+-ATPase
estrane
series
estrane
ske]eton
of
simplest
(6). we
its
As s t a r t i n g used
14~-hydroxy-
3-methoxy-8~,9~-1,3,5(10)-estratrien-17-one ences
6 and 7 ) .
tiary using
hydroxy a
group
mixture
methy]si]y])
The s t e r i c a ] ] y
of
in
y]si]y] crude
ether
acetamide,
II,
the
mixture
and (8-10).
reaction
(TMS) p r o t e c t e d product
alcohol
I
(refer-
hindered was
eno]
ter-
si]y]ated
trimethy]si]y]imidazo]e,
N,N-dimethy]formamide sired
the
(I)
strong]y
com-
bis(tri-
trimethy]ch]orosi]ane In also ether
addition afforded III
by mass s p e c t r a
to the
the
STEROIDS 53/1-2
de-
trimeth-
as p r o v e n which
in
in
the
displayed
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
molecular
ions
Although
of the
sufficiently physical
both
II
and I I I ,
bis-trimethylsilyl
to
stable
methods
or
109
to
derivative
allow
III
was
characterization
undergo it
thin-layer
preparative)
chromatography,
the ketone I I
by traces of acids or even
by
(even
was reconverted i n t o on
prolonged
action of s i l i c a gel, such as in column chromatography. The
IH
NMR
spectrum of I I
exhibits a characteristic
s i n g l e t of t r i m e t h y l s i l y l o x y group singlet
of angular
methyl a t
at
~
=
0.28,
a
8 = 1.06 , a s i n g l e t o f
methoxy group a t ~ = 3.72, and a m u l t i p l e t of
aromatic
protons. W i t t i g reaction o f ketone I I with y l i d e , generated in
situ
from
triphenylmethylphosphonium
sodium s a l t of dimethyl good
yield
converted
the by
sulfoxide
methylene
derivative
hydroboration
17-hydroxymethyl
(10),
derivative
and
iodide
by
afforded
in
IV, which
oxidation
V (11).
into
C17 i n
derivative
Infrared
spectrum
a band
at
drogen
bond
STEROIDS 53/1-2
V I was d e t e r m i n e d of
VI
3 458 cm -1 (12)
in
between
January-February 1989
the
pro-
The c o n f i g u r a t i o n a t by s e v e r a l
tetrachloromethane
confirming
the
The reactioq was
accompanied by p a r t i a l loss o f the t r i m e t h y l s i l y l t e c t i n g group leading t o d i o l VI.
was
methods. exhibits
an i n t r a m o l e c u l a r hydroxy
groups
hyat
C14
110
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
=
J-
=
o ~ cHao~ o ~ s II
III
oH
c_H.~
C)
CH~O
c~o V
IV
IX
~
VI
/cooc~ s
CH~o
~ /
VII
cooc~
C
X Scheme
VIII
XI
XIV
1
STEROIDS 53/1-2
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCIlC SIDE CHAIN
and
C20.
Although
ented Bide chain, of
proves the presence of
the product
17~- and 1 7 ~ - h y d r o x y m e t h y l
ination
with
the
by d e r i v a t i z a t i o n or
this
still
VI w i t h
a ~-ori-
m i g h t be a m i x t u r e
derivatives.
17~-derivative of
111
Such c o n t a m -
was n o t e x c l u d e d even
phenylboric
acid
in ether
with large excess of carbonyldiimidazole in dimeth-
ylformamide because n e i t h e r of
these
the desired d e r i v a t i v e
V I I I in a
V I I or
y i e l d , some unreacted s t a r t i n g Question of the side chain
experiments gave quantitative
alcohol being l e f t .
The
attachment has been f i n a l l y
solved by 1H NMR spectroscopy. The
IH NMR
spectrum
(at
200.059 MHz) e x h i b i t s
several separated groups of proton s i g n a l s I)
which
w e r e assigned
on
experiments. I r r a d i a t i o n of 1.78
the
the
(see
Table
basis o f decoupling C17-H signal
at ~ =
s i m p l i f i e d the m u l t i p l e t o f protons a t C20 to
an
AB system with geminal constant JJJ = 11.0 Hz. The v i c i n a l coupling constants J17,20 = 3.2 and 1.8
Hz
indi-
cate t h a t the hydroxyl group i s oriented towards the Dring,
in agreement with
bridge
between C20-OH
red (IR) spectra. three-proton
the
intramolecular
and C14-0H
The C18 methyl
found by the infraprotons
appear as a
gives no sign
of splitting
even after weighting free induction decay
(FID) by the
STEROIDS 53/1-2
singlet that
hydrogen
Januaw-February1989
112
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
exponential
function,
ral s i g n a l chemical
width shift
substituents
to
of
of
ring
D was
on t h e
the
intensity
ment
at
ring
the of
D indicates
from
singlet
Effect
(NOE),
the
-
8.9~,
depending
from
on
the
the ring
C17-endo-methylene
groups
other
this
because only the
spatial From
C17-CH20H
groups
found
#-cis-arrangement
ring
D in
the
result
analysis The
of
alcohol
chlorochromate
in
VI,
of
V
XII was
(vide
by
pro-
configurations
of
C13-methyl
and
cis is
each
compatible
C14-0H
and
we can d e -
substituents the
to
a NOE e n h a n c e -
whole
been c o n f i r m e d
on t h e synthetic
by s p e c t r o -
infr~).
oxidized
dichloromethane
induced
method of
of
in
the
enhance-
for
all
on
integrated
IR spectrum,
and t h u s
has a l s o ester
the
is
relative
oriented
necessary
diol
( C 2 0 - H a)
the
are
in
the
This
D,
of
S = 3.78
cis-configuration
rive
diol
the
configuration
proximity
the
groups
on t h e
possible
the
configura-
(C18-H)
Overhauser
substituents
scopic
~ = 1.08 at
6.5
our
The r e l a t i v e
changes of
at
of
arrangement
that
signal
As f o l l o w s
series.
the
proton
being
ment.
C18 t o
the
cessing.
with
The s e n s i t i v i t y
and h y d r o x y m e t h y l e n e
determined
irradiation
Hz.
homogeneous.
methyl
of
Nuclear
0.08
protons
configurationally tion
resulting in narrowing the natu-
to
with give
STEROIDS 53/1-2
pyridinium
the
aldehyde
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
Table
113
I
C h a r a c t e r i s t i c IH NMR Data (200 MHz) f o r Diol VI Signal
Assignment
7.04 6.72 6.62 3.78 3.77 3.77 3 47 2 93 2 76 2 63 2 41 1 78 1,30
d dd d dd
s m dd m m m m m
m s
to 2.30 1.08
IX, which was
(J=8)(1H) (J=8 and 2 ) ( 1 H ) (J=2)(1H) (J=11 and 1 . 8 ) ( 1 H ) (3H)
C1-H C2-H C4-H C20-H a OCH3
(IH) (J=11 and 3,2)(IH) (IH) (JAB=I7)(1H) (JAB=I7)(1H)
OH C20-H b Cg-H C6-H a C6-H b
(1H)
(1H) (11H) (3H)
C17-H 3 x C18-H
p u r i f i e d by
filtration
of alumina and then used f u r t h e r
through a column
in the Wittig-Horner
condensation
with methyl
condensation
afforded the TMS-protected
methyl ester XI
(13) in a good y i e l d , s i m i l a r l y as the
analogous reac-
t i o n of the
aldehyde
leading
the e t h y l
to
diethylphosphonoacetate.
The
IX with triethylphosphonoacetate ester
X (13). However, the a t -
tempted cleavage of TMS p r o t e c t i n g group of the 14#-hydroxy group
of XI with a mixture
of zinc
bromide and
t i t a n i u m t e t r a c h l o r i d e (14) was accompanied by e l i m i n a t i o n . The mixture of
STEROIDS 53/1-2
alcohol X I I and
January-February1989
dehydro compound
114
Drasar et ah 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
/coocH.3
/
C.~ac~.3
XIV
cN~
c%o XII
XIII
/
c~o czH~
C.,~iO
h XVI
XV
/
cooc~
H XVII
%
00 OH
O430 XVIII
CH3°
XIX
XX
Scheme 2
STEROIDS 53/I-2
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
115
of the type X I I I obtained was d i f f i c u l t
to separate and
was not f u r t h e r i n v e s t i g a t e d . Therefore, we prepared the alcohol
XII
using
an
analogous sequence in the unprotected 14-hydroxy s e r i e s (15). The d i o l VI was oxidized with chromium t r i o x i d e pyridine
complex in
aldehyde jected
dichloromethane
to
derivative
Wittig-Horner
XII
characterized 370
spectrum
in by
and
corresponding
ester,
to
reaction
giving
a good y i e l d , its
mass
further the
phenolic ether,
matic and
with
the The
alcohol
spectrum
XII
(molecular
characteristic expected
methyl
14~-hydroxy
ions),
structure.
and aromatics.
was ion fully
The
IR
d i s p l a y s , in
S i m i l a r l y , the a d d i t i o n to aro-
e t h y l e n i c protons, s i g n a l s due to
ether, methyl e s t e r , and one angular methyl. o f only
one signal o f
the methyl
astereoisomer side chain. apparent from
with unchanged
(200 MHz; see Table 2).
January-February 1989
methyl
The pres-
pure
di-
1?~-configuration of the
The E-configuration o f the coupling
a
a t C13 ( i . ~ . ,
C18-protons) i n d i c a t e s t h a t the e s t e r X I I i s
STEROIDS 53/1-2
the
e x h i b i t s bands due to an alcohol, unsaturated
200 MHz IH NMR spectrum
ence
give
XIV which, without c h a r a c t e r i z a t i o n , was sub-
diethylphosphonoacetate
m/z
to
the double bond i s
constant 3J20,21 = 15.6 Hz
116
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
Table
2
C h a r a c t e r i s t i c IH NMR Data (200 MHz) f o r Ester X I I
Signal 7 20 7 02 6 71 6 61 5 64 3 77 3 72 2 92 2 80 271 2 42 2.08 to 1,88 0.93
1.40
As
a
dd d dd d dd s s m m m m m m s
model
synthesis, the
Assignment ( J = 1 5 . 6 and 1 0 . 6 ) ( 1 H ) (J=8.3)(1H) ( J = 8 . 3 and 2 . 8 ) ( 1 H ) (J=2.8)(1H) ( J = 1 5 . 6 and 0 . 5 ) ( 1 H ) (3H) (3H) (1H) (1H) (1H) (2H) (3H)
C20-H Cl-H C2-H C4-H C21-H -COOCH 3 -OCH 3 C9-H C6-H a C6-H b
(3H)
3 x C18-H
reaction
we a l s o
for
elaborated
14#-trimethylsilyloxy
and X I
to
the
Lewis acids. character group
free It
of
the
alcohols
protected
room
checked
temperature with
by
compounds
1 II,
-
the
in
4 h. V,
II,
V,
mineral
or
according
These
and X I
to
the
trimethylsily]
treatment
tetrachloride for
with
~queous hydrochloric or
deblocking
derivatives
that,
alcohol,
dichloromethane-methanol
at
in
by r e a c t i o n
h a s been f o u n d
and t i t a n i u m
above-described
a method for
group
c a n be r e m o v e d w i t h
bromide
the
acid with
in zinc
dichloromethane reactions and f o u n d
STEROIDS 53/1-2
were to
be
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
preparatively
usable with
all
these cases,
to
minor
tography Of t h e
longer
side-products [TLC]),
reagents
(detected
by t h i n - l a y e r - c h r o m a -
separable tin
with
Table
3
this
series
acids
by
rise
chromatography.
tetrachloride
in dichloro-
The e x p e r i m e n t a l are given
gave
In
with
methane was n o t s u i t a b l e . tained
two compounds.
treatment
easily tried,
the former
117
results
ob-
i n T a b l e 3.
Cleavage of 1 4 ~ - T r i m e t h y l s i l y l o x y D e r i v a t i v e s
Starting compound II a IIb II c IId
IIe V a XI d
Reagent
Medium
Reaction time, h
ZnBr2 CH2Cl2 HCl CH2CI2-CH30H TiCl 4 CH2Cl2 ZnBr2+ T i C l 4 CH2Cl 2 SnC14 CH2C12 ZnBr 2 CH2C12 ZnBr2+ TiC14 CH2C12
4 4 4
Product
Yield
I I
71% 76%
I
64~
I
68~
4 1 1
decomposition 56% VI
1.5
decomposition
a S t a r t i n g compound (20 mg) was dissolved in d i c h l o r o methane (1 mL), and anhydrous zinc bromide (25 mg) was added to the s o l u t i o n . A f t e r the r e a c t i o n , the mixture was p a r t i t i o n e d between ether and potassium hydrogen carbonate s o l u t i o n , and the ethereal e x t r a c t s were d r i e d , evaporated, and chromatographed on s i l i c a gel. b Methanol (0.4 mL) and 37% aqueous h y d r o c h l o r i c acid (0.1) were added to a s o l u t i o n o f the s t a r t i n g compound (20 mg) in dichloromethane ( I mL) and the reaction mixture was processed as described in footnote a, c Same procedure a, 25 mg o f t i t a n i u m t e t r a c h l o r i d e . d Same procedure a, 25 mg of 1:1 mixture. e Same procedure a, 25 mg o f t i n t e t r a c h l o r i d e .
STEROIDS 53/1-2
January-February1989
I~8
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
As a second model Hornet
reaction,
reaction of the
formyl-5~-androstane acetate and methyl
we studied the Wittig-
chemically (XV)
very
with
simple
17/3-
triethylphosphono-
diethylphosphonoacetate,
leading
to
esters XVI and XVll. In all aldehydes
cases,
the
IX, XIV,
homogeneous
studied
and
products
XV of
double bond as evidenced
condensations
afforded
stereochemically
E-configuration
at the 20,21
by the high coupling
of the C20-H and C21-H protons
of the
constant
(16 Hz).
For evaluating the s y n t h e t i c reactions, as well as f o r checking p u r i t y of the products, we i s o c r a t i c reverse-phase
an
high pressure l i q u i d chromato-
graphy (HPLC) method, using
methanol-water (9:1; v / v )
as the mobile phase. The chromatographic Table 4) also includes
elaborated
analysis
compounds present
t i o n mixtures in the synthesis of
ketone
(see
in the reacI
from
diketone X V I I I , the unsaturated hydroxyketone
the
XIX, and
the bisdehydro d e r i v a t i v e XX. Since
the
key
compound X I I
compound,
was s y n t h e s i z e d
we t e s t e d
the
as a
potentially
active
inhibitory
a c t i v i t y (see references 16 and 17) of t h i s
STEROIDS 53/1-2
Na+K+-ATPase
January-February 1989
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
Table
119
4
Separation of Reverse-Phase
Synthetic Estrane Derivatives by HPLC i n M e t h a n o l - W a t e r 9 : 1 ( v / v )
Compound
I II IV
Capacity f a c t o r k'
Retention time t R (min) 3.57 9.33 37.50 11.88 5,17 10.55 8.96 5,67 3.83 3,33 5.67
V
VI X XI XII XVIII XIX XX
0.53 3.00 15.09 4.10 1.22 3,53 2.85 1.43 0.64 0.43 1.43
Apparatus: Milton Roy/LDC system Support Unit I pump, s t a i n l e s s steel column (250 x 4 mm i . d . ) packed with SEPARON Si C18 (10 jum), UV-detector UVM-4 (Developmental Workshops o f the Czechoslovak Academy o f Sciences), and a K n a u e r No. 36.00.00 loop valve. Samples were applied in dichloromethane (10juL) and eluted with methanol-water (9:1 v/v) at 25°C, flow rate I mL/min, pressure 4.82 MPa (685 p . s . i . ) , d e t e c t i o n at 254 rim.
compound
and o f
compound Vl
(Table
only very low i n h i b i t o r y a c t i v i t y ,
5).
We h a v e f o u n d
comparable with t h a t
of 3 , 1 4 , 1 7 - t r i o l s derived from analogous skeletons (6). However,
an
evaluation
of
r e l a t i o n s h i p s f o r such new types of
STEROIDS 53/1-2
January-February 1989
structure-activity xenobiotics
based
120
Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
on s y n t h e t i c
will
steroid
skeletons
of unnatural
ring f u s i o n
require more experimental m a t e r i a l . This
study describes a new method of construction
of the side chain in cardenolide analogues in which the butenolide r i n g i s replaced unsaturated steroid
ester
skeleton
However,
the
alcohol X I I ,
grouping with
target exhibits
an
by on
a
similar
of
low
conjugated
synthetic
unsaturated
compound only
a
racemic
8~,9~-fusion.
the synthesis, the inhibitory
activity
towards Na+K+-ATPase (see Table 5).
Table
5
I n h i b i t i o n of Na+K+-ATPase by Xenobiotics VI and X I I Molar [mol.L - I ] concentration 10 - 4 3.10 -5 10 - 5 3.10 -6
I n h i b i t i o n by VI
I n h i b i t i o n by X I I
6% 1% _
Conditions as described in Na+K+-ATPase used (EC3.6.t.3)
25% 11% 4% _ references 16 and 17, w a s from pig k i d n e y (16).
EXPERIMENTAL The melting block (VEB A n a l y t i k , corded on a UR-20
points were determined on a Boetius Dresden, GDR). IR spectra were re( Zeiss, Jena, GDR) spectrometer,
STEROIDS 53/I-2
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121
wavenumbers are given in cm- I . IH NMR spectra were measured on a BS-468 (60 MHz, Tesla Brno CSSR) and Varian XL-200 (200 MHz, Palo A l t o USA) instrument in d e u t e r i o chloroform with t e t r a m e t h y l s i l a n e as i n t e r n a l standard, chemical shifts are given in the ~-scale (ppm), coupling constants (J) and signal widths (W) in Hz. A l l the s p e c t r a l parameters w e r e obtained by the f i r s t order analysis. Mass s p e c t r a were o b t a i n e d w i t h an AEI-901 i n s t r u m e n t , u n l e s s s t a t e d o t h e r w i s e . Preparative
chromatography
was
performed
on
columns o f s i l i c a g e l a c c o r d i n g t o P i t r a (60 - 120 ~um, Service Laboratories of the Institute of Organic Chemistry and Biochemistry, Praha); t h i n - l a y e r chromatography was c a r r i e d out on s i l i c a gel G according t o S t a h l (Woelm) o r on S i l u f o l UV-254 p l a t e s (Kavalier, C z e c h o s l o v a k i a ) ; d e t e c t i o n by s p r a y i n g with 96~ sulfuric acid and heating or by UV l i g h t ( C h r o m a t o l i t e ) . Solutions w e r e dried over anhydrous magnesium s u l f a t e , and solvents w e r e removed on a r o t a t o r y e v a p o r a t o r a t 40 - 50 °C and 2 2.5 kPa. Analytical s a m p l e s were d r i e d o v e r p h o s p h o r u s p e n t o x i d e a t a b o u t 25 Pa. rac-3-Methoxy-14B-trimethvlsilyloxv-8~.g~-estra-l.3.5(lO)-%rien-17-one ( I I ) T r i m e t h y l s i l y l i m i d a z o l e(6 mL; 41 mmol), b i s ( t r i m e t h y l silyl)acetamide (6 mL; 24 mmol) and t r i m e t h y l c h l o r o s i l a n e (4 mL; 32 mmol) were added t o a s o l u t i o n of hydroxyketone I (2 g; 6.6 mmol) in N,N-dimethylformamide (20 mL). The mixture was s t i r r e d a t 65°C f o r 7 h, water (100 mL) was added, and the mixture was extracted w i t h ether (3 x 50 mL). The combined ethereal e x t r a c t s were dried and taken down, the residue was applied onto a column of s i l i c a gel (100 g) and, a f t e r standing f o r I h, chromatographed in benzene-light petroleum ( 1 : 1 ) . The m a i n f r a c t i o n was evaporated, and the o i l y residue was mixed with l i g h t petroleum, the separated c r y s t a l s were f i l t e r e d and washed with l i g h t petroleum, y i e l d 1.96 g (83%) o f t r i m e t h y l s i l y l ether I I , m.p. 147 t o 150 °C. Mass spectrum (m/z): 372 (M+), 282 (M H O S i ( C H 3 ) 3 ) . I H NMR s p e c t r u m ( d e u t e r i o c h l o r o f o r m , extern a l l o c k ) : 0 . 2 8 s (9H, ( C H 3 ) 3 S i O - ) , 1.06 s (3H, a n g u l a r methyl), 3 . 7 2 s (3H, CH30- ) , 6.61 to 7.09 m (3H, aromatic protons). For C22H3203Si (372.6) calculated: 70.92~ C, 8 . 6 6 ~ H; f o u n d : 71.23~ C, 8.84% H.
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Drasar et aI: 19-NORSTEROIDS W l l H ACY(LIC SIDE CHAIN
rac-17-Methylene-8~.9~-estra-1.3,5(10)-triene3 . 1 4 B - d i o l 3-Methyl Ether 1 4 - T r i m e t h y l s i l y l e t h e r ( I V ) Sodium h y d r i d e ( 4 8 1 mg; o f 50% suspension i n mineral o i l ; 10 mmol) was washed w i t h l i g h t petroleum (3 x 20 mL) under argon, mixed w i t h d i m e t h y l s u l f o x i d e (37 mL), and heated to 65°C for 1 h under argon. Triphenylmethylphosphonium iodide ( 3 . 3 7 g; 8 . 3 4 mmol) was added a t room temperature, the m i x t u r e was s t i r r e d f o r 30 min~and the p r o t e c t e d ketone I I (732 mg; 2 mmol) was added. After stirring at 65°C for 20 h, the r e a c t i o n m i x t u r e was p a r t i t i o n e d between s a t u r a t e d ammonium c h l o r i d e s o l u t i o n and e t h e r . The aqueous phase was e x t r a c t e d w i t h e t h e r , the combined e t h e r e a l e x t r a c t s were d r i e d , concentrated i_Qn vacuo, and chromatographed on a column o f s i l i c a gel (100 g) i n l i g h t petroleum. The main f r a c t i o n afforded 501 mg (69%) o f ether IV, m.p. 75 t o 77°C. Mass spectrum : ( m / z ) : 370 ( M + ) , 280 (M - H O S i ( C H 3 ) 3 ) . 1H NMR s p e c t r u m (deuteriochloroform): 0 . 9 4 s (3H, a n g u l a r m e t h y l ) , 3.60 s (3H, C H 3 0 - ) , 4 . 6 3 m (2H, C=CH2, W = 1 0 ) , 6 . 4 7 t o 7 . 0 5 m (3H, a r o m a t i c p r o t o n s ) . F o r C23H3402Si ( 3 7 0 . 6 ) c a l c ulated: 74.54% C, 9.29% H; found: 74.63% C, 9.29% H. rac-17B-Hydroxvmethy1-8E,9~-estra-1,3,5(10)-tri@q~$ . 1 4 B - d i o l 3-Methyl Ether 1 4 - T r i m e t h v l s i l y l Ether (V) L i t h i u m aluminium h y d r i d e (100 mg; 2.6 mmol) i n ether (4 mL) was added a t -15°C t o a s o l u t i o n o f methylene d e r i v a t i v e IV (100 mg; 0.27 mmol) and boron t r i f l u o r i d e e t h e r a t e ( 0 . 5 mL; 0.41 mmol) i n e t h e r (3 mL). The m i x t u r e was s t i r r e d a t -15°C f o r 1.5 h and then a t room temperature f o r 30 min, decomposed w i t h s a t u r a t e d sodium s u l f a t e s o l u t i o n (5 mL) and water (10 mL) and the aqueous phase was e x t r a c t e d w i t h e t h e r . The ethereal extracts were dried, the solvent was evaporated, and the residue was dissolved in t e t r a h y d r o f u r a n (3 mL). A q u e o u s potassium h y d r o x i d e (10%; 2.5 mL) and hydrogen peroxide (30% aqueous solution; 1 . 5 mL) w e r e added a t O°C. After stirring at O°C f o r 30 m i n , t h e m i x t u r e was d i l u t e d with water and extracted with ether. The e x t r a c t was d r i e d and t a k e n down, and t h e r e s i d u e was a p p l i e d onto a silica gel column (100 g ) , and e l u t e d s u c c e s s i v e l y with benzene, benzene-ether (9:1), and b e n z e n e - e t h e r (1:1). The main fraction a f f o r d e d 44 mg (46%) o f s i l y l d e r i v a t i v e V;
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further fractions gave d i o l V I . Compound V was o b t a i n e d as a g l a s s y substance. Mass s p e c t r u m (m/z): 388 (M+), 298 (M - H O S i ( C H 3 ) 3 ) , 370 (M - H20), 262 (298 CH3OH). IR s p e c t r u m (chloroform): 3630 (OH), 2845, 1262, 1252) (CH3~-)'IHN 1611, 1582, 1502 ( a r o m a t i c r i n g ) , 842 (Si-C . MR spectrum, (tetrachloromethane, external lock): 0.10 s (9H, ( C H 3 ) 3 S i O - ) , 0 . 9 9 s (3H, angular methyl), 3.4 to 4.0 m (2H, -CH2OH), 3 . 7 3 s (3H, C H 3 0 - ) , 6 . 5 0 t o 7 . 1 0 m (3H, a r o m a t i c p r o t o n s ) . For C23H3603Si (388.6) calculated: 71.08~ C, 9.34~ H; f o u n d : 71.27~ C, 9.56~ H. rac-17B-Hvdroxymethyl-8~.9~-estra-1.3.5(10)-triene3,14~-di01 3-Methyl Ether (VI) Further fraction in the chromatography of alcohol V afforded diol Vl as a g l a s s y m a t e r i a l i n t h e y i e l d o f 34 mg ( 4 0 ~ ) . Mass s p e c t r u m (m/z): 298 (M H20), IR s p e c t r u m (tetrachloromethane): 2845, 1270, 1243 ( C H 3 0 - ) , 1611, 1582, 1504 (aromatic ring), 3642, 3601 (OH), 3458 ( h y d r o g e n b o n d ) . 1H NMR s p e c t r u m ( d e u t e r i o chloroform, external lock): 0.96 s (3H, angular methyl), 3.30 to 4.10 m (2H, -CH2OH), 3.73 s (3H, CH30-), 6.50 to 7.10 m (3H, aromatic protons). For C20H2803 (316.4) calculated: 75.91% C, 8.92% H; f o u n d : 75.67~ C, 9.28% H. rac-(20E)-21-Methoxycarbonyl-19-nor-8~.9~-oreana1,~,~(10).20-tetraene-3.14B-diol 3-Methyl Ether 14-Trimethylsilyl Ether (XI) Alcohol V (270 mg; 0.69 mmol) was d i s s o l v e d in dichloromethane (5 mL), and p y r i d i n i u m c h l o r o c h r o m a t e (300 mg) was added. The m i x t u r e was s t i r r e d at room temperature for 1 h and f i l t e r e d t h r o u g h a column o f a l u m i n a (30 g; R e a n a l , activity II), which was t h e n washed w i t h benzene. The f i l t r a t e was e v a p o r a t e d and the residue (containing aldehyde IX) dissolved in 1 , 2 - d i m e t h o x y e t h a n e (10 mL). Sodium h y d r i d e (168 mg o f 50% s u s p e n s i o n i n m i n e r a l o i l ) was washed w i t h light petroleum (3 x 25 mL) under a r g o n , and l a y e r e d w i t h 1 , 2 - d i m e t h o x y e t h a n e ( 1 7 . 5 mL). M e t h y l d i e t h y l p h o s p h o n o a c e t a t e ( 0 . 6 5 mL; 3 . 5 mmol) was added to the stirred mixture at room t e m p e r a t u r e under argon and t h e stirring was c o n t i n u e d for further 20 m i n . The above-described solution of aldehyde IX in 1 , 2 - d i m e t h o x y e t h a n e was t h e n added, and t h e m i x t u r e was stirred
STEROIDS 5311-2
at
room temperature
January-February1989
for
2 h under
argon.
Water
124
Drasar et ah 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
was added (5 mL) and t h e v o l a t i l e
organic
solvents
were
distilled off i__on vacuo. The r e s i d u e was mixed w i t h e t h e r (50 mL) and washed w i t h water (3 x 20 mL). After d r y i n g and e v a p o r a t i o n o f the s o l v e n t , the residue was chromatographed on a column o f s i l i c a gel (50 g) i n light petroleum-benzene ( 3 : 2 , 250 mL) and then in benzene (300 mL). The main f r a c t i o n gave 290 mg (95%) o f compound Xl as a glassy substance. M a s s spectrum
(m/z): 442 (M+), 352 (M H O S i ( C H 3 ) 3 ) , 240 (352 C6H802), 159 (CH3OCIoH9), 157 (CH3OCIoH7). IR s p e c t r u m (tetrachloromethane): 1651, 1724 (-COOCH3), 1500, 1610 (aromatic ring), 840 ( S i ( C H 3 ) 3 ) . 1H NMR s p e c t r u m ( t e t rachloromethane, external l o c k ) : 0 . 0 5 s (9H, S i ( C H 3 ) 3 ) , 0 . 7 8 s (3H, a n g u l a r m e t h y l ) , 3 . 5 4 s (3H, -COOCH3), 3 . 5 0 s (3H, -OCH3), 5 . 5 8 bd (1H, C21-H, J = 1 6 ) , 6 . 2 0 t o 7.15 m (4H, aromatic protons + C20-H). For C20H3804Si (442.7) calculated: 70.55% C, 8.65% H; f o u n d : 70.84% C, 8.90% H. rac-(20E)-21-Ethoxvcarbonyl-19-nor-8~.9E-oreQna1.3.5(10).20-tetraene-3,14~-diol 3-Methyl Ether 14-Trimethylsilyl Ether (X) The t i t l e compound was p r e p a r e d as d e s c r i b e d f o r t h e methyl ester XI, using triethylphosphonoacetate instead of methyl diethylphosphonoacetate in the same m o l a r r a t i o . Compound X was o b t a i n e d as a glassy substance i n 87% y i e l d , m a s s spectrum (m/z): 456 (M+), 366 (M -
(CH3)3SiOH), 321. 1H NMR s p e c t r u m (tetrachloromethane e x t e r n a l lock): 0 . 0 5 s (9H, O S i ( C H 3 ) 3 ) , 0 . 8 4 s (3H, angular methyl), 1.13 t (3H, -OCH2CH3, J = 7 . 5 ) , 3.57 s (3H, CH30- ), 3.99 q (2H, -OCH2CH3, J=7.5), 5.60 bd ( I H , C21-H, J20,21=16), 6.20 t o 7.00 (4H, aromatic protons + C20-H). For C27H4004Si (456.7) calc u l a t e d : 71.00% C, 8.83% H; found: 71.23% C, 8.91% H.
rac-(20E)-21-Methoxvcarbonvl-19-nor-8E. 9~-orean~1.3.5(10).20-tetraene-3.14B-diol 3-Methyl Ether (XII) P y r i d i n e ( 0 . 8 7 mL; 10.7 mmol) was added u n d e r stirring and c o o l i n g w i t h ice to a suspension o f chromium t r i o x i d e (540 mg; 5.40 mmol) and anhydrous magnesium sulfate (450 mg) in dichloromethane (20 mL). After s t i r r i n g a t O°C f o r 20 min, d i o l VI (200 mg, 0.55 mmol) i n dichloromethane (10 mL) was added t o the m i x t u r e . The m i x t u r e was s t i r r e d a t 0 °C f o r 30 min and a t room
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125
temperature f o r 30 min, filtered through an alumina column (30 g; Reanal, a c t i v i t y I I ) , which was washed w i t h ether-benzene ( 2 : 1 ) , and the f i l t r a t e s , c o n t a i n i n g the aldehyde XIV, were taken down. Sodium hydride (154 mg, of 50% suspension in mineral o i l , 3.2 m m o l ) was washed w i t h l i g h t petroleum (3 x 20 mL) under argon and mixed with 1,2mdimethoxyethane ( 3.5 mL ) and methyl diethylphosphonoacetate (0.6 mL; 3.35 mmol). A f t e r s t i r r i n g a t room temperature f o r 10 min, aldehyde XIV (220 mg) in 1,2-dimethoxyethane (4 mL) was added, the m i x t u r e was s t i r r e d a t room temperature f o r 7 h and p a r t i t i o n e d between water (100 mL) and e t h e r (50 mL). The aqueous phase was e x t r a c t e d w i t h e t h e r (3 x 40 mL), and the combined e t h e r e a l e x t r a c t s were d r i e d and evaporated. C r y s t a l l i z a t i o n from e t h e r - l i g h t petroleum gave 140 mg (68% from the s t a r t i n g VI) o f e s t e r X I I , m.p. 153 - 157°C. Mass spectrum (m/z): 370 (M+), 339 (M CH30- ), 352 (M H20 ), 240 (352 H2C=CH-CH=CH-COOCH3), 225 (240 - CH3- ). IR s p e c t r u m (chloroform): 3610 (OH), 1713, 1652, 1162 (C=C-COOCH3), 2845, 1267, 1242 ( C H 3 0 - ) , 1642, 1588, 1505 ( a r o m a t i c ring). IH NMR spectrum ( d e u t e r i o c h l o r o f o r m ) : 0.91 s (3H, angular m e t h y l ) , 3.74 s (3H, CH30-), 3.70 s (3H, COOCH3), 5 . 6 2 d (1H, C21-H, J = 16), 6.50 to 7.45 m (4H, a r o m a t i c p r o t o n s + C20-H). For C23H3004 ( 3 7 0 . 5 ) calculated: 74.56% C, 8.16%H; f o u n d : 74.70~ C, 8.36% H. (20E)-21-Ethoxvcarbonvl-5~-pregn-20-ene (XVI) Sodium h y d r i d e (415 mg o f 50% s u s p e n s i o n i n m i n e r a l oil; 86 mmol) was washed w i t h l i g h t p e t r o l e u m (3 x 10 mL) under a r g o n , mixed w i t h 1 , 2 - d i m e t h o x y e t h a n e (10 mL~ and t h e n with triethylphosphonoacetate ( 1 . 7 1 mL; 8 . 6 mmol). The m i x t u r e was s t i r r e d a t room t e m p e r a t u r e f o r 20 min and a l d e h y d e XV ( r e f e r e n c e 18, 500 mg; 174 mmol) in 1,2-dimethoxyethane (5 mL) was added d r o p w i s e . The r e a c t i o n m i x t u r e was s t i r r e d a t room temperature f o r 12 h, t a k e n down j n v a c u o , a n d t h e r e s i d u e was p a r t i t i o n e d between water (50 mL) and e t h e r (50 mL). The aqueous phase was e x t r a c t e d w i t h e t h e r (3 x 30 mL) and the combined ethereal extracts were dried, evaporated, d i s s o l v e d i n benzene, and f i l t e r e d t h r o u g h a column of silica g e l (50 g ) , w h i c h was t h e n washed w i t h benzene. Evaporation of the filtrate afforded ester XVI as an amorphous solid (474 mg; 76%). IR spectrum (chloroform): 1721, 1651, 1184 (C=C-COOR). 1H NMR s p e c -
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Drasar et al: 19-NORSTEROIDS WITH ACYCLIC SIDE CHAIN
trum ( d e u t e r i o c h l o r o f o r m ) : 6.93 dd (IH, C20-H, J20,17 = 7.5, J20,21 = 16), 5.75 d (1H, C21-H, J20,21 = 16), 4.20 q (2H, OCH2CH3, J = 7 ) , 1.31 t (3H, OCH2CH3, J = 7), 0.71 and 0 . 6 5 2 s (2 x 3H, a n g u l a r m e t h y l s ) . For C24H3802 (358.6) calculated: 80.39~ C, 1 0 . 6 8 ~ H; f o u n d : 8 0 . 6 6 ~ C, 1 0 . 7 1 ~ H.
(20E)-21-Methoxycarbonvl-5~-Dregn-20-ene (XVII) The compound was prepared as described above f o r e s t e r XVI using methyl d i e t h y l p h o s p h o n o a c e t a t e (1.6 mL; 8.6 mmol) i n s t e a d o f t r i e t h y l p h o s p h o n o a c e t a t e . The same i s o l a t i o n gave the g l a s s y e s t e r XVII as an o i l (436 mg; 74~). IR spectrum ( c h l o r o f o r m ) : 1722, 1651, t439 (C=C-COOR). 1H NMR s p e c t r u m ( d e u t e r i o c h l o r o f o r m ) : 6.98 dd (1H, C20-H, J 1 7 , 2 0 = 7 . 5 , J 2 0 , 2 1 = 1 6 ) , 5 . 7 4 d (1H, C21 - H ' J 2 0 , 2 1 = 1 6 ) , 3 . 7 0 s (3H, CH30CO), 0 . 6 4 and 0 . 8 0 2 x s (2 x 3H, a n g u l a r m e t h y l s ) . For C23H3602 (344.5) calculated: 80.18~ C, 10.53~ H; found: 80.39~ C, 10.76~ H. N~Glear Overhauser E f f e c t (NOE) Exoeriment w i t h D i o l VI a t 200 MHz Before the measurement oxygen was t h o r o u g h l y driven o f f by i n t r o d u c i n g argon into solution of the diol in CDC13 t o p r e v e n t s p i n r e l a x a t i o n . Changes o f i n t e g r a t e d intensities of the singlet at S = 1 . 0 8 on i r r a d i a t i o n of the proton signal at ~ = 3.78 were followed. Free induction d e c a y ( F I D ) f o r t h e n o r m a l s p e c t r u m was s u b tracted f r o m FID f o r t h e s p e c t r u m o b t a i n e d by d e c o u p l ing of the proton a t ~ = 3 . 7 8 so as t o e l i m i n a t e the internal standard (tetramethylsilane) signal. The difference spectrum obtained by t r a n s f o r m a t i o n of the resulting FID gave a p o s i t i v e s i g n a l a t ~ = 1 . 0 8 . The relative NOE e n h a n c e m e n t v a l u e amounted t o 6 . 5 - 8.9% relative to the tetramethylsilane reference signal.
ACKNOWLEDGMENTS The
authors
are
indebted
to
Miss.
H.
Kapi~kov&
for
measurement o f the IR s p e c t r a and t o Dr. I J. Smol~kov~ l f o r t h e i r i n t e r p r e t a t i o n , t o Mrs. J. J e l l n k o v a and Dr. D. ~aman f o r the 60 MHz IH NMR s p e c t r a , t o Dr. A. Trka for mass spectral measurements, and t o the s t a f f o f the A n a l y t i c a l Laboratory headed by Dr. J. Hor&~ek f o r the elemental analyses. A l l of t h e m are from the
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127
Prague I n s t i t u t e o f O r g a n i c C h e m i s t r y and B i o c h e m i s t r y . T h e i r t h a n k s a r e a l s o due t o K.N. Dzhandzhugazyan o f M. M. Shemyakin Institute of Bio-organic Chemistry, Moscow, f o r measurements o f Na+K+-ATPase i n h i b i t i o n . NOTES A part o f t h i s work has been p u b l i s h e d i n a p r e liminary form (19). P a r t CCCXXXV i n the series On S t e r o i d s , Part CCCXXXIV see ( 2 0 ) . REFERENCES 1. 2. 3.
4.
5.
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