Structure of (−)flavoskyrin, a colouring matter of penicillium islandicum sopp nrrl 1175

Tetrahedron Lettere moo.9. pp 7% - 736

STRUCTUREOF(OF Shujiro

(Reoeivsd

m.p.

islandicum

quinone

which

compound

14

January

Sciences

SOPP

[9/D

formula

was

Sankawa

and

revised

of rugulosin

recently,

unplausible.

homologous preceding

- 295 ‘(dioxane), supposed

which

was elucidated

the structures

of flavoskyrin

The reactions

compounds report

which

thecium

derived

(4) to revise

has recently

verrucaria

in pyridine

proposed

( - )flavoskyrin the dimeric

the chemical

properties

supported

Japan

a yellow

colouring

to be a monomeric (2) referring

1972)

matter

modified

Zahn

of

anthra-

and Koch’s

but a dimeric by the mass

from

Schw .)Ditmer is transformed

structures

by Zahn

spectrum,

and Koch

Penicillium ex Fr.

(5),

formulated

islandicum while

compounds

m/e 526 (M

whose -H20),

755

of flavoskyrin ( IIa ) have

is converted Sopp

NRRL

(IIb).

into (-)rugulosin

1175,

with thionyl

and

Myro-

chloride

(=dichrysophanol(8,8’))(IV).

that ( - )flavoskyrin formula,

in the

structure

and the above-mentioned

molecular

of the

as described

by a dimeric

on treatment

it has been suggested

anthraquinone

‘-dimer

compound

have been reexamined

into ( + )dianhydrorugulosin

of the model

I ,l

a

(3) and the structures

of pyridine , (-)flavoskyrin

of ( - )flavoskyrin, modified

R

as being

( Ia ) and the model

of IIa as being

the structure

HO

formerly

by the same process

been isolated

(Alb.et

Referring

monomer

Shibata

of Tokyo.

( Ia ) was proposed

It has now been found that by the action (III)

Shoji

( IIa ) (3) as the model.

the structure

become

Britain.

1175

NRRL

0 As

in Great

COLOURINGMATTER

,University

1 I 75 (1) was

NRRL

a structural

printed

1972; reoeived in UK for publication27 J--Y

215”(decomp.), Sopp

Ushio

Ogihara,

of Pharmaceutical

Penicillium for

Yukio

in Japn

( - )Flavoskyrin,

A

)FLAvoSIWRIN,

PENICILLIUM ISLANDICUM

Seo,

Faculty

Pergmon FTess.

1972.

C 30H240,0,

506 (M - H2 - 2H20).

findings

in

is not a has been

lo.

7% The

UV absorption

compound

hydroxyls

.

spectrum

of 2 methyls,

The multiplets

atom bearing at 1 and

signals

a hydroxyl

of ( - )flavoskyrin

from chrysophanol

The n.m.r.

with it.

showing

Table

curve

( DC ) (4) prepared

chromophore dimer

spectral

of -CH2-

revealed

is almost

to indicate

that flavoskyrin

of ( - )flavoskyrin

2 olefinic coupled

indicated

and 2 aromatic

ring

with the multiplet

the position

of the C-C

superimposable

on that of the model

possesses

the same

that it is an unequivalent

protons,

and 4 enolic

of the proton

linkage

9

attached

connecting

or phenolic

to the carbon

two monomeric

moieties

1’ . I.

The N.m.r.

Spectrum

Fig.

of ( - )Flavoskyrin

(in d8 Dioxane)

6 ppm

1

log E ;:

CH3 -C_H2-&H-

2.5h3.0

H

Olefinic

H

Phenolic Enolic

(m

4.06(m) “““““.’ 4 6. ( d ) .... ........ .

-CH2-C\$H Arom.

2.10

1.96

OH

OH

Considering

the n.m .r.

The IR spectral

4.30(m) 4 9. ( d )

.

6.55

6.96

6.13

6.31

9.50

15.76

11.21

14.13

and UV spectral

absorption

by the effect

of the neighbouring

( 4 1.

0

HO

)

at 1715 cm

-1

4.0 ;

2y

3.0,

evidences

carbon

HO

400

-(-)Flavoskyrin

------

( - )flavoskyrin

. assigned 1s

quarternary

3uo

. 1 5oonm DC

must be formulated

to the carbonyl

at C

(9)

atom as shown in the model

which

as ( Ib ).

is twisted

compounds

( IIb ,c )

_..

5%

“I

I

Il.

’

I .I

w 0

,HO

HO

.

w ( Ib)

OH

’

HO

( III .)

Acknowledgements The authors wish to thank ‘Ministry of Education and HBansha for Thanks are also due to Dr. S. Minami,Research Laboratory,Dainihon Seiyaku Co.Ltd. supplying information about the occurrence of (-)rugulosin in Myrothecium.

grants. for

REFERENCES 1) B.H. 2) S.

Howard

Shibata,

T.

T . Ikekawa 3) K.

Ikekawa

and T.

U.

Minami

Sankawa

:

Private

andM.

Biochem.J., Takido,

56 ,

Pharm.

56 (1954).

Bull.(Tokyo),

Kishi , Chem. Pharm . Bull .(Tokyo)

Zahn and H. Koch,

4) S . Seo, 5) S.

and H. Raistrick,

Ber.deutsch.chem.Ges.7_L, and S . Shibata, Communication.

Preceding

,z

,

~72 (1938). paper

4 ,303 (1956);

889 (I 960).

S.

Shibata,