- Email: [email protected]
Diterpenoids from Isodon adenoloma
Phyfochemistry, Vol. 31, No. 12, pp. 42374240, Printed in Great Britain.
1992
DITERPENOIDS ZHANG
0031-9422/92 $5.00+0.00 Q 1992 Pergamon Press Ltd
FROM ISODON ADENOLOMA
RONG PING,* ZHANG HONGJIE, LIN ZHONG~EN, ZHEN YULIN~ and SUN HANDoNGt
Laboratory of Phytochemistry,
Kunming Institute of Botany, Academia Sinica, Kunming 650204, China; *Yunnan Traditional Chinese Medical College, Kunming, China (Received 10 March 1992)
Key Word Index-Isodon
adenoloma; Labiatae; ent-kaurene; diterpene, adenolin A-E; NMR.
Abstract-Five new ent-kaurene diterpenoids, adenolin A-E, and a known compound, longikaurln D were isolated from the air-dried leaves of Isodon adenoloma. The structures were established by spectroscopic means.
INTRODUCTION Isodon udenoloma (Hand-Mazz) Hara, is a perennial herb grown in south-eastern China. Its chemical constituents have not been investigated previously. From the ethereal extract of dried leaves of this plant, six diterpenoids (l-6), including five new ent-kaurene diterpenoids (l-5) were isolated. RESULifS AND DISCUSSION The leaves gave longikaurin D (6) [l], as well as five new diterpenoids, named adenolin A (l), B (2), C (3), D (4) and E (5). Adenolin A (I), C25H3609 ([Ml’ at m/z 480), showed the presence of a tertiary methyl, eight methylenes (including three oxygenated methylenes), six methines (including two oxygenated methines), three quaternary carbons, a hemiacetal carbon, a ketonic carbon, two acetoxy groups, and a methoxy group in its ‘H and 13C NMR spectra (Tables 1 and 2). These facts coupled to a consideration of the structures of diterpenoids from the genus Zsodon [2, 31 led to the presumption of 1 having a ent-7a,20-epoxy-kaurene-hemiacetal-15-one skeleton. The ‘H-‘H COSY allowed the assignment of all proton signals in 1, which was confirmed by a ‘H-‘3CCOSY experiment. A doublet of doublet signal of S 4.33 (H-6a) coupled with two doublet signals at 6 1.61 (H-5/?) and 6.23 (OH-6/l). A triplet signal at 6 5.41 (H-l l/?) coupled with a multiplet signal at 6 2.13 (H-128) and 1.81 (H-9/$. The H128 signal coupled with a doublet of doublet signal at 62.01 (H-12a), which coupled with a multiplet signal at 6 2.77 (H-13@. The H-13cr signal coupled with a doublet of doublet signal at 6 2.61 (H-14/?) and a multiplet signal at 62.96 (H-16@, which coupled with two doublet of doublet signals at 63.71 and 63.59 (H,-17). In the ‘H-‘H 2D COSY spectrum of 1, the coupling correlation of two H-19 protons (6 4.65 and 4.35), two H-20 protons (6 4.53 and 4.1 l), two H-17 protons (6 3.71 and 3.59), two H-14 protons (63.01 and 2.61), and two H-3 protons (6 1.81 and 0.99) could also be observed. The series of coupling correlation from H-98 to H-14fi and the loss of
PAuthor to whom correspondence should be addressed.
correlated signals between 6 2.01 (H-12a) and 6 5.41 (H1 lb), between 6 2.13 (H-12/3) and 6 2.77 (H-13cr), as well as between 6 2.77 (H-13~) and S 3.01 (H-14c() established that the C-ring has a hemichair conformation. The signal at 6 5.41 was assigned to H-11/?. In the ‘H-‘H2D DQF COSY (double quantum filter COSY) [4] spectrum of 1, we were able to observe several W-coupling correlations. The proton signal at 64.35 (H,-19) coupled with the proton signals at 6 1.61 (H-5b), 4.65 (H,-19) and 0.99 (H38). The H-SD signal coupled with the proton signal at 6 4.53 (H,-20). The proton signal at 6 4.11 (H,-20) coupled with the proton signal at 6 1.81 (H-9/?). Based on the above results, the A-, B- and C-ring conformations of 1 were established as chair, boat and her&hair, respectively. Finally, the ‘H-‘H 2D COSY and ‘H-‘H 2D DQF COSY made it possible for us to deduce the structure of 1: H,-1 + H,-2 -+ H-3/l (through 2D COSY) + Ha-19 (W-coupling, through 2D DQF COSY) + H-58 (W-coupling) H,- 19, W-coupling) ((-+ H-6c(, through 2D COSY) -+ Ha-20 (W-coupling) + H,-20 (through 2D COSY) + H-9/? (W-coupling) + H-11/l + H-128 -+ H-12a -+ H-13~ (- H-148 -+ H-14~) -+ H-16a -+ Hz-l7 (through 2D COSY). The ‘H and “CNMR spectra of 1 (Tables 1 and 2) showed the presence of one secondary hydroxy group, two acetoxyl groups and one methoxy group, which were provisionally assigned as OH-68, OAc-llcr, OAc-19 and OMe-17, respectively. In the ‘H-‘H 2D DQF COSY spectrum of 1, we could find the Zigzag-coupling correlation signals of the proton signal at 6 1.94 (OAc) with those at S 4.65 and 4.35 (H,-19), and we could also find the Zigzag-coupling signal of the proton signal at 62.08 (OAc) with that at 6 5.41 (H-l l/3). So, the two acetoxyl groups were established as OAc-19 and OAc-1 ICC,respectively. The upfield shift of the 13CNMR signal for C-12 caused by a ygauche shielding effect between MeO-17 and H-12/3 confirmed the cotiguration of the MeO-17 group as /J. The ‘H-‘H 2D NOESY gave correlated signals between the Hz-17 signals and the methoxy proton signal, which led to assignment of the methoxy group on C-17. The proton signal at 6 4.33 (dd, J = 11.3, 6.5 Hz) was assigned to H&Y due to the coupling constant with H-5/? (6 1.61, lH, d, 5=6.5 Hz) [S]. All the above data identified adenolin A (1) as 6fi,7b-dihydroxy-lla,l9-diacetoxy-l7fimethoxy-ent-7/?,20-epoxy-kauran-15-one.
4237 PHY 31:12-N
ZHANG RUNG PING et al.
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18 OAc
OAc
OAc 1
2
3
4
5
6
OAc
Adenolin B (2), C,zH,,O, ([Ml’ at m/z 422), showed similar ‘H and 13C NMR spectral data to those of longikaurin D (6) (Tables 1 and 2). An extra lowfield signal at 6 3.96 (1H. t, J= 8.0 Hz) in 2 was attributed to Hl/I compared with that of 6. The downfield shifts of C-2 and C-10 in the r3CNMR spectrum of 2 revealed the presence of a OH-l group, which assigned a-configuration owing to the upfield shift of C-20 caused by a ygauche shielding effect between OH-la and Ha-20 [2,6]. Adenolin B was, therefore, determined to be la,6/?,7/$llatetrahydroxy-19-acetoxy-ent-7B,20-epoxy-kaur-l6-en1S-one. Adenolin C (3), C,,H,,O, ([Ml’ at m/z 438), differs from 1 only in the loss of one acetoxy group (Tables 1 and 2). The upfield shift of the H-l 18 signal from 6 5.41 (lH, t, 5=4.3Hz) in 1 to 64.40 (lH, overlap, H-11/I) in 3 established that the hydroxy group at C-l 1 in 3 replaced the acetoxyl group at C-11 in 1. Thus, adenolin C was elucidated as 6/?,7/?,1 la-trihydroxy-19-acetoxy17p-methoxy-ent-7jI,20-epoxy-kauran15-one. Adenolin D (4), C23H3407 ([Ml+ at m/z 422), showed nearly identical ‘H and 13CNMR data as 1 except for replacement of the Hz-19 and C-19 signals of 1 with, Me19 signals in 4 (Tables 1 and 2). This indicated that the acetoxyl-19 group in 1 is replaced by a Me-19 group in 4. This was proved by the disappearance of the y-gauche effect on C-19 and C-3 due to OAc-19. Thus, compound 4 was deduced to be 6P,7fi-dihydroxy-1 la-acetoxy-17flmethoxy-ent-7P,20-kauran-15-one. Adenolin E (5) C23H340s ([Ml” at m/z 438), was shown to have the same 6P-hydroxy-17/3-methoxy-7a,20epoxy-kauran-7-hemiacetal-lS-one skeleton as 4 by comparing the ‘H and ’ 3C NMR data of the two compounds Tables 1 and 2). As in the case of adenolin B (2), we could infer the presence of a OH-la or OAc-lr, but the striking downfield shift of the H-l signal in 5 showed the presence of OAc-la. The upfield shift of the H-14a signal (6 1.96, d, J = 8.8 Hz) in 5 showed no effect on the OH-l la (or OAc1 la). However, we could find H-l 1 and C-l 1 signals in the ‘H and r3C NMR spectra of 5 [S], which means that C-l 1 must be located by a /?-hydroxy group. Consequently, we
assign the structure of 6/?,7&11/?-trihydroxy-la-acetoxy17-methoxy-ent-7#&20-epoxy-kauran16-one to 5.
EXPERIMENTAL General. Mps: uncorr; [a];? MeOH; IR: KBr; UV: MeOH, ‘HNMR (400.134 MHz), i3CNMR (100.622 MHz, broad band and DEPT), and 2D NMR: pyridine-d,, TMS as int. standard, EIMS: 70 eV. The dried and powdered leaves (6.7 kg) of Isodon adenoloma, collected in Zhongdian, Yunnan, China in Nov. 1989, were extracted with Et,0 to give a green residue after evapn of the Et,O. The residue was refluxed in MeOH with charcoal (50 g) for 1 hr then filtered ( x 3) to give a yellow soln. The M&H soln was evapd and the residue (214g) was subjected to CC (silica gel) with CHCl, and increasing proportions of eluting Me&O-CHCl,. Fractions were monitored by TLC. All components were further purified by recrystallization and/or silica gel CC yielding adenolin A (1) (2.35 g), B (2) (70 mg), C (3) (85 mg), D (4) (56 mg). E (5) (540 mg) and longikaurin D (6) (1.75 g). Adendin A (1). Needles, mp 182-184”, [a]Y -121.7”; UV A”,::” nm (E): 201 (2290); IR Y,,, cm-‘: 3370-3280, 1735-1715, 1372,1235,1050; MS m/z: 480 [M] +, 448,420,403,388,332,301, 149, 105,91,43 (base peak). (Found: C 63.07, H 7.63. C,,H,,O, requires: C 62.43, H 7.55.) Adenolin B (2). Needles, mp 253-255”, [alA -204.5”; UV ueoH nm (8): 239.5 (8263); IR Y,, cm-i: 3482, 3315, 1730, 1698, &n,,, 1635, 1234, 1082, 1058, 1027; MS m/z: 422 [Ml’, 362 [M -MeCO,H]+,344,313,301,269,211, 199, 161, 105,91.79,55, 43 (base peak). (Found: C 62.23, H 7.21. C,rH,,O, requires: C 62.55, H 7.16.) Adenolin C (3). Needles, mp 214-216”, [a]h9 -100.8”; UV AE:p nm (8): 203 (3754); IR Y,,, cm -‘: 3515, 3275, 1730, 1714, 1255, 1245; MS m/z: 438 [MI’, 378, 346,302,285,213, 105,97, 79, 55, 43 (base peak). (Found: C 63.19, H 7.90. C2sH3.,08 requires: C 63.00, H 7.82.) Adenolin D (4). Needles, mp 204206”, [a]Y - 78 9”. UV 1:::” nm (E): 201 (2194); IR v,,, cm-‘: 3295, 1723, 1717, ;240, 1050; MS m/z: 422 [Ml’, 388, 344, 301, 269, 151, 105, 91, 79, 55, 43
148 16K 17a 17b Me-18 Me-19 19a 19b 20a 20b AcO AcO OH-6 OH-l OH-11 OMe
128 13a 14a
1lD 12a
9B lla
38 5s 6ct
3a
28
2a
3.23 s
4.65 d, 4.35 d, 4.53 d, 4.11 d, 2.08 s 1.94 s 6.23 d, 6.97 d, 10.9 7.87 d, 2.7 6.48 d, 2.2
6.42 d, 11.1
3.27 s
6.26 br s
4.52 d, 9.0 4.22 d, 9.6 2.12 s
11.3
d, 11.1 Cj,11.1 d, 9.0 d, 9.0
4.73 4.46 5.24 4.15
10.8 10.8 9.8 9.8
4.81 d, 4.46 d, 5.24 d, 4.37 d, 1.98 s
11.0 11.0 9.4 9.4
5.98 s 5.33 s 1.47 s
5.44 t, 4.2 1.99 overlap 2.10 overlap 2.79 m 3.04d, 12.0 2.65 dd, 3.0, 12.0 2.99 m 3.74 dd, 4.2, 10.2 3.62 dd, 9.8, 10.2 1.23 s 1.07 s
4.39 br s 2.19 dd, 9.8, 15.6 1.84 overlap 2.91 m 3.64 d, 11.6 2.59 dd, 3.1, 11.6 299m 3.78 dd, 4.5, 10.3 3.64 t, 10.3
5.41 t, 4.3 2.01 overlap 2.13 overlap 2.77 m 3.01 d, 12.6 2.61 dd, 3.2, 12.6 2.96 m 3.71 dd, 4.5, 10.2 3.59 t, 10.2 1.35 s
4.58 br s 2.63 dd, 9.4, 15.0 1.90 overlap 3.15 dd, 3.8, 9.4 3.64 d, 11.6 2.56 dd, 3.8, 11.6
4 1.47 m 1.26 overlap 1.36 overlap 1.36 overlap 2.01 overlap 1.05 overlap 1.72 d, 6.5 4.24 overlap 2.01 overlap
3 2.32 br d, 13.2 1.33 overlap 1.40 overlap 1.40 overlap 1.84 overlap 1.08 br t, 3.2 1.65 d, 6.4 4.38 dd, 6.4, 11.1 1.53 d, 5.0
3.96 br t, 8.0 1.82 m 1.18 m 1.93 overlap 1.20 m 1.75 d, 7.6 4.50 dd, 7.6, 10.9 1.66 d, 3.5
1.50 br d, 1.31 1.27 overlap 1.30 overlap 1.30 overlap 1.81 overlap 0.99 ddd, 3.2, 9.6, 10.0 1.61 d, 6.5 4.33 dd, 6.5, 11.3 1.81 d, 4.3
la
1B
2
1
H
Table 1. IH NMR spectra of compounds l-6
6.31 d, 11.0 8.81 br s 5.69 br s 3.2 s
4.58 d, 10.5 4.37 d 10.5 2.07 s
2.54 overlap 2.54 overlap 2.84 m 2.54 overlap 1.64 overlap 2.97 ddd, 4.0, 4.7, 9.8 3.72 dd, 4.7, 10.3 3.54 dd, 9.8, 10.3 1.12 s 1.08 s
5.42 dd, 5.0, 11.6 1.64 overlap 1.30 overlap 2.23 ddd, 4.1, 4.6, 13 1.30 overlap 1.6 d, 4.9 4.14 dd, 4.9, 11 1.96 d, 8.8 4.63 m
s
6.44 d, 3.88
6.90 d, 11.0
4.72 d, 11.0 4.48 d, 11.0 5.27 dd, 1.6, 9.0 4.21 dd, 1.5, 9.0 1.94 s
5.98 s 5.30 s 1.45 s
4.42 q, 4.3 2.51 dd, 10.0, 15.0 1.71 dd, 4.3, 15.0 3.13 dd, 4.3, 10.0 3.62 d, 11.6 2.57 dd, 4.3, 11.6
2.33 br d, 13.2 1.34 overlap 1.34 overlap 1.34 overlap 1.90 br d, 13.4 1.09 ddd, 3.3, 13.4, 13.4 1.66 dd, 1.5, 7.4 4.48 dd, 7.4, 11.0 1.55 d, 4.31
6
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C 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 OMe
OAc
1 29.8 18.4 35.9 37.6 62.3 73.7 95.9 60.2 53.1 37.0 68.6 28.4 29.1 29.6 223.0 57.3 69.1 27.9 66.6 69.1 58.7 170.7 169.7 21.6 20.6
R0~f.2
Table
2. 13CNMR
spectra
2
3
4
5
6
73.2 29.9 33.6 37.6 62.3 74.2 96.3 59.8 54.9 43.1 66.9 39.4 34.8 27.1 211.2 154.3 115.5 27.8 66.2 66.9
29.6 18.5 36.3 37.6 63.1 74.0 96.2 60.9 54.5 37.8 65.3 31.7 29.4 29.4 224.5 58.1 69.3 27.7 66.7 69.3 58.7
30.1 18.7 41.5 34.1 61.5 74.7 95.9 60.2 53.3 37.0 68.8 28.4 29.1 29.7 223.1 57.3 69.1 33.9 22.4 68.5 58.9
76.2 24.4 38.7 34.0 62.8 74.3 95.6 61.2 58.8 40.5 62.9 32.2 30.0 29.8 224.7 58.7 68.9 32.6 21.9 64.7 58.7
30.8 18.7 36.4 37.6 61.8 74.3 96.4 60.0 54.7 37.8 65.6 41.5 34.9 27.4 210.9 154.4 115.5 28.4 67.1 69.6
170.7 20.7
170.8 20.9
169.8 21.6
170.1 21.6
170.7 20.7
(base peak). (Found: C 65.47, H 8.04. C23H3407 requires: C 65.38, H 8.11.) Adenolin E (5). Needles, mp 213.5-215”, [a];!’ -82.9”; UV A:$“’ nm (6): 202 (2532); IR v,,, cn-‘: 3418,3266, 1733, 1715, 1235;MSm/z:438[M]+,420[M-H,0]+,406[M-MeOH]+, 378 [M-MeCO,H]+, 360 [378-H,O]+, 300, 257, 195, 161, 121, 105, 91, 85, 55, 43 (base peak). (Found: C 63.15, H 7.83. Cz3H3.,08 requires: C 63.00, H 7.82.) Longikaurin D (6). Needles, mp 225-227”, [a]Y - 150.0”; UV IZ/zH nm (E): 239 (7263); IR v,, cm-‘: 3510,3275, 3218, 1716, 1700,1636,1244; MS m/z: 406 [M] +, 388 [M -H,O] +, 364,346, 328, 297, 269, 203, 149, 121, 107, 95, 83, 55, 43 (base peak). (Found: C 65.46, H 7.45, C,,H,,O, requires: C 65.01, H 7.44.) Acknowledgement-The authors identification of plant material.
thank
PING et al.
Professor
Li Xiwen for
of compounds
l-6
REFERENCES
” 2’ 3,
4’ 5
’ 6,
Fujita, T., Takeda, Y. and Yang Shingu, T. (1981) Heterocycles 16, 227. Huang Hao, Zhang Hognjie and Sun Handong (1990) Phytochemistry 29, 259 1. Li Chunbao, Sun Handong and Zhou Jun. (1988) Acta Chimica Sinica 46, 657. Rance, T. M., Sorensen, 0. W., Bodenhansen, G., Wagner, G., Ernst, R. R. and Wiizhrich, K. (1983) Eiochem. Biophys. Res. Commun. 117,458. Shen Xiaoyu, Sun Handong, Isogai, A. and Suzuki, A. (1990) Acta Botanica Sinica 32, 711. Chen Yiping, Sun Handong and Lin Zhongwen (1990) Acta Botanica Sinica 32 292.
1992
DITERPENOIDS ZHANG
0031-9422/92 $5.00+0.00 Q 1992 Pergamon Press Ltd
FROM ISODON ADENOLOMA
RONG PING,* ZHANG HONGJIE, LIN ZHONG~EN, ZHEN YULIN~ and SUN HANDoNGt
Laboratory of Phytochemistry,
Kunming Institute of Botany, Academia Sinica, Kunming 650204, China; *Yunnan Traditional Chinese Medical College, Kunming, China (Received 10 March 1992)
Key Word Index-Isodon
adenoloma; Labiatae; ent-kaurene; diterpene, adenolin A-E; NMR.
Abstract-Five new ent-kaurene diterpenoids, adenolin A-E, and a known compound, longikaurln D were isolated from the air-dried leaves of Isodon adenoloma. The structures were established by spectroscopic means.
INTRODUCTION Isodon udenoloma (Hand-Mazz) Hara, is a perennial herb grown in south-eastern China. Its chemical constituents have not been investigated previously. From the ethereal extract of dried leaves of this plant, six diterpenoids (l-6), including five new ent-kaurene diterpenoids (l-5) were isolated. RESULifS AND DISCUSSION The leaves gave longikaurin D (6) [l], as well as five new diterpenoids, named adenolin A (l), B (2), C (3), D (4) and E (5). Adenolin A (I), C25H3609 ([Ml’ at m/z 480), showed the presence of a tertiary methyl, eight methylenes (including three oxygenated methylenes), six methines (including two oxygenated methines), three quaternary carbons, a hemiacetal carbon, a ketonic carbon, two acetoxy groups, and a methoxy group in its ‘H and 13C NMR spectra (Tables 1 and 2). These facts coupled to a consideration of the structures of diterpenoids from the genus Zsodon [2, 31 led to the presumption of 1 having a ent-7a,20-epoxy-kaurene-hemiacetal-15-one skeleton. The ‘H-‘H COSY allowed the assignment of all proton signals in 1, which was confirmed by a ‘H-‘3CCOSY experiment. A doublet of doublet signal of S 4.33 (H-6a) coupled with two doublet signals at 6 1.61 (H-5/?) and 6.23 (OH-6/l). A triplet signal at 6 5.41 (H-l l/?) coupled with a multiplet signal at 6 2.13 (H-128) and 1.81 (H-9/$. The H128 signal coupled with a doublet of doublet signal at 62.01 (H-12a), which coupled with a multiplet signal at 6 2.77 (H-13@. The H-13cr signal coupled with a doublet of doublet signal at 6 2.61 (H-14/?) and a multiplet signal at 62.96 (H-16@, which coupled with two doublet of doublet signals at 63.71 and 63.59 (H,-17). In the ‘H-‘H 2D COSY spectrum of 1, the coupling correlation of two H-19 protons (6 4.65 and 4.35), two H-20 protons (6 4.53 and 4.1 l), two H-17 protons (6 3.71 and 3.59), two H-14 protons (63.01 and 2.61), and two H-3 protons (6 1.81 and 0.99) could also be observed. The series of coupling correlation from H-98 to H-14fi and the loss of
PAuthor to whom correspondence should be addressed.
correlated signals between 6 2.01 (H-12a) and 6 5.41 (H1 lb), between 6 2.13 (H-12/3) and 6 2.77 (H-13cr), as well as between 6 2.77 (H-13~) and S 3.01 (H-14c() established that the C-ring has a hemichair conformation. The signal at 6 5.41 was assigned to H-11/?. In the ‘H-‘H2D DQF COSY (double quantum filter COSY) [4] spectrum of 1, we were able to observe several W-coupling correlations. The proton signal at 64.35 (H,-19) coupled with the proton signals at 6 1.61 (H-5b), 4.65 (H,-19) and 0.99 (H38). The H-SD signal coupled with the proton signal at 6 4.53 (H,-20). The proton signal at 6 4.11 (H,-20) coupled with the proton signal at 6 1.81 (H-9/?). Based on the above results, the A-, B- and C-ring conformations of 1 were established as chair, boat and her&hair, respectively. Finally, the ‘H-‘H 2D COSY and ‘H-‘H 2D DQF COSY made it possible for us to deduce the structure of 1: H,-1 + H,-2 -+ H-3/l (through 2D COSY) + Ha-19 (W-coupling, through 2D DQF COSY) + H-58 (W-coupling) H,- 19, W-coupling) ((-+ H-6c(, through 2D COSY) -+ Ha-20 (W-coupling) + H,-20 (through 2D COSY) + H-9/? (W-coupling) + H-11/l + H-128 -+ H-12a -+ H-13~ (- H-148 -+ H-14~) -+ H-16a -+ Hz-l7 (through 2D COSY). The ‘H and “CNMR spectra of 1 (Tables 1 and 2) showed the presence of one secondary hydroxy group, two acetoxyl groups and one methoxy group, which were provisionally assigned as OH-68, OAc-llcr, OAc-19 and OMe-17, respectively. In the ‘H-‘H 2D DQF COSY spectrum of 1, we could find the Zigzag-coupling correlation signals of the proton signal at 6 1.94 (OAc) with those at S 4.65 and 4.35 (H,-19), and we could also find the Zigzag-coupling signal of the proton signal at 62.08 (OAc) with that at 6 5.41 (H-l l/3). So, the two acetoxyl groups were established as OAc-19 and OAc-1 ICC,respectively. The upfield shift of the 13CNMR signal for C-12 caused by a ygauche shielding effect between MeO-17 and H-12/3 confirmed the cotiguration of the MeO-17 group as /J. The ‘H-‘H 2D NOESY gave correlated signals between the Hz-17 signals and the methoxy proton signal, which led to assignment of the methoxy group on C-17. The proton signal at 6 4.33 (dd, J = 11.3, 6.5 Hz) was assigned to H&Y due to the coupling constant with H-5/? (6 1.61, lH, d, 5=6.5 Hz) [S]. All the above data identified adenolin A (1) as 6fi,7b-dihydroxy-lla,l9-diacetoxy-l7fimethoxy-ent-7/?,20-epoxy-kauran-15-one.
4237 PHY 31:12-N
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OAc
OAc 1
2
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6
OAc
Adenolin B (2), C,zH,,O, ([Ml’ at m/z 422), showed similar ‘H and 13C NMR spectral data to those of longikaurin D (6) (Tables 1 and 2). An extra lowfield signal at 6 3.96 (1H. t, J= 8.0 Hz) in 2 was attributed to Hl/I compared with that of 6. The downfield shifts of C-2 and C-10 in the r3CNMR spectrum of 2 revealed the presence of a OH-l group, which assigned a-configuration owing to the upfield shift of C-20 caused by a ygauche shielding effect between OH-la and Ha-20 [2,6]. Adenolin B was, therefore, determined to be la,6/?,7/$llatetrahydroxy-19-acetoxy-ent-7B,20-epoxy-kaur-l6-en1S-one. Adenolin C (3), C,,H,,O, ([Ml’ at m/z 438), differs from 1 only in the loss of one acetoxy group (Tables 1 and 2). The upfield shift of the H-l 18 signal from 6 5.41 (lH, t, 5=4.3Hz) in 1 to 64.40 (lH, overlap, H-11/I) in 3 established that the hydroxy group at C-l 1 in 3 replaced the acetoxyl group at C-11 in 1. Thus, adenolin C was elucidated as 6/?,7/?,1 la-trihydroxy-19-acetoxy17p-methoxy-ent-7jI,20-epoxy-kauran15-one. Adenolin D (4), C23H3407 ([Ml+ at m/z 422), showed nearly identical ‘H and 13CNMR data as 1 except for replacement of the Hz-19 and C-19 signals of 1 with, Me19 signals in 4 (Tables 1 and 2). This indicated that the acetoxyl-19 group in 1 is replaced by a Me-19 group in 4. This was proved by the disappearance of the y-gauche effect on C-19 and C-3 due to OAc-19. Thus, compound 4 was deduced to be 6P,7fi-dihydroxy-1 la-acetoxy-17flmethoxy-ent-7P,20-kauran-15-one. Adenolin E (5) C23H340s ([Ml” at m/z 438), was shown to have the same 6P-hydroxy-17/3-methoxy-7a,20epoxy-kauran-7-hemiacetal-lS-one skeleton as 4 by comparing the ‘H and ’ 3C NMR data of the two compounds Tables 1 and 2). As in the case of adenolin B (2), we could infer the presence of a OH-la or OAc-lr, but the striking downfield shift of the H-l signal in 5 showed the presence of OAc-la. The upfield shift of the H-14a signal (6 1.96, d, J = 8.8 Hz) in 5 showed no effect on the OH-l la (or OAc1 la). However, we could find H-l 1 and C-l 1 signals in the ‘H and r3C NMR spectra of 5 [S], which means that C-l 1 must be located by a /?-hydroxy group. Consequently, we
assign the structure of 6/?,7&11/?-trihydroxy-la-acetoxy17-methoxy-ent-7#&20-epoxy-kauran16-one to 5.
EXPERIMENTAL General. Mps: uncorr; [a];? MeOH; IR: KBr; UV: MeOH, ‘HNMR (400.134 MHz), i3CNMR (100.622 MHz, broad band and DEPT), and 2D NMR: pyridine-d,, TMS as int. standard, EIMS: 70 eV. The dried and powdered leaves (6.7 kg) of Isodon adenoloma, collected in Zhongdian, Yunnan, China in Nov. 1989, were extracted with Et,0 to give a green residue after evapn of the Et,O. The residue was refluxed in MeOH with charcoal (50 g) for 1 hr then filtered ( x 3) to give a yellow soln. The M&H soln was evapd and the residue (214g) was subjected to CC (silica gel) with CHCl, and increasing proportions of eluting Me&O-CHCl,. Fractions were monitored by TLC. All components were further purified by recrystallization and/or silica gel CC yielding adenolin A (1) (2.35 g), B (2) (70 mg), C (3) (85 mg), D (4) (56 mg). E (5) (540 mg) and longikaurin D (6) (1.75 g). Adendin A (1). Needles, mp 182-184”, [a]Y -121.7”; UV A”,::” nm (E): 201 (2290); IR Y,,, cm-‘: 3370-3280, 1735-1715, 1372,1235,1050; MS m/z: 480 [M] +, 448,420,403,388,332,301, 149, 105,91,43 (base peak). (Found: C 63.07, H 7.63. C,,H,,O, requires: C 62.43, H 7.55.) Adenolin B (2). Needles, mp 253-255”, [alA -204.5”; UV ueoH nm (8): 239.5 (8263); IR Y,, cm-i: 3482, 3315, 1730, 1698, &n,,, 1635, 1234, 1082, 1058, 1027; MS m/z: 422 [Ml’, 362 [M -MeCO,H]+,344,313,301,269,211, 199, 161, 105,91.79,55, 43 (base peak). (Found: C 62.23, H 7.21. C,rH,,O, requires: C 62.55, H 7.16.) Adenolin C (3). Needles, mp 214-216”, [a]h9 -100.8”; UV AE:p nm (8): 203 (3754); IR Y,,, cm -‘: 3515, 3275, 1730, 1714, 1255, 1245; MS m/z: 438 [MI’, 378, 346,302,285,213, 105,97, 79, 55, 43 (base peak). (Found: C 63.19, H 7.90. C2sH3.,08 requires: C 63.00, H 7.82.) Adenolin D (4). Needles, mp 204206”, [a]Y - 78 9”. UV 1:::” nm (E): 201 (2194); IR v,,, cm-‘: 3295, 1723, 1717, ;240, 1050; MS m/z: 422 [Ml’, 388, 344, 301, 269, 151, 105, 91, 79, 55, 43
148 16K 17a 17b Me-18 Me-19 19a 19b 20a 20b AcO AcO OH-6 OH-l OH-11 OMe
128 13a 14a
1lD 12a
9B lla
38 5s 6ct
3a
28
2a
3.23 s
4.65 d, 4.35 d, 4.53 d, 4.11 d, 2.08 s 1.94 s 6.23 d, 6.97 d, 10.9 7.87 d, 2.7 6.48 d, 2.2
6.42 d, 11.1
3.27 s
6.26 br s
4.52 d, 9.0 4.22 d, 9.6 2.12 s
11.3
d, 11.1 Cj,11.1 d, 9.0 d, 9.0
4.73 4.46 5.24 4.15
10.8 10.8 9.8 9.8
4.81 d, 4.46 d, 5.24 d, 4.37 d, 1.98 s
11.0 11.0 9.4 9.4
5.98 s 5.33 s 1.47 s
5.44 t, 4.2 1.99 overlap 2.10 overlap 2.79 m 3.04d, 12.0 2.65 dd, 3.0, 12.0 2.99 m 3.74 dd, 4.2, 10.2 3.62 dd, 9.8, 10.2 1.23 s 1.07 s
4.39 br s 2.19 dd, 9.8, 15.6 1.84 overlap 2.91 m 3.64 d, 11.6 2.59 dd, 3.1, 11.6 299m 3.78 dd, 4.5, 10.3 3.64 t, 10.3
5.41 t, 4.3 2.01 overlap 2.13 overlap 2.77 m 3.01 d, 12.6 2.61 dd, 3.2, 12.6 2.96 m 3.71 dd, 4.5, 10.2 3.59 t, 10.2 1.35 s
4.58 br s 2.63 dd, 9.4, 15.0 1.90 overlap 3.15 dd, 3.8, 9.4 3.64 d, 11.6 2.56 dd, 3.8, 11.6
4 1.47 m 1.26 overlap 1.36 overlap 1.36 overlap 2.01 overlap 1.05 overlap 1.72 d, 6.5 4.24 overlap 2.01 overlap
3 2.32 br d, 13.2 1.33 overlap 1.40 overlap 1.40 overlap 1.84 overlap 1.08 br t, 3.2 1.65 d, 6.4 4.38 dd, 6.4, 11.1 1.53 d, 5.0
3.96 br t, 8.0 1.82 m 1.18 m 1.93 overlap 1.20 m 1.75 d, 7.6 4.50 dd, 7.6, 10.9 1.66 d, 3.5
1.50 br d, 1.31 1.27 overlap 1.30 overlap 1.30 overlap 1.81 overlap 0.99 ddd, 3.2, 9.6, 10.0 1.61 d, 6.5 4.33 dd, 6.5, 11.3 1.81 d, 4.3
la
1B
2
1
H
Table 1. IH NMR spectra of compounds l-6
6.31 d, 11.0 8.81 br s 5.69 br s 3.2 s
4.58 d, 10.5 4.37 d 10.5 2.07 s
2.54 overlap 2.54 overlap 2.84 m 2.54 overlap 1.64 overlap 2.97 ddd, 4.0, 4.7, 9.8 3.72 dd, 4.7, 10.3 3.54 dd, 9.8, 10.3 1.12 s 1.08 s
5.42 dd, 5.0, 11.6 1.64 overlap 1.30 overlap 2.23 ddd, 4.1, 4.6, 13 1.30 overlap 1.6 d, 4.9 4.14 dd, 4.9, 11 1.96 d, 8.8 4.63 m
s
6.44 d, 3.88
6.90 d, 11.0
4.72 d, 11.0 4.48 d, 11.0 5.27 dd, 1.6, 9.0 4.21 dd, 1.5, 9.0 1.94 s
5.98 s 5.30 s 1.45 s
4.42 q, 4.3 2.51 dd, 10.0, 15.0 1.71 dd, 4.3, 15.0 3.13 dd, 4.3, 10.0 3.62 d, 11.6 2.57 dd, 4.3, 11.6
2.33 br d, 13.2 1.34 overlap 1.34 overlap 1.34 overlap 1.90 br d, 13.4 1.09 ddd, 3.3, 13.4, 13.4 1.66 dd, 1.5, 7.4 4.48 dd, 7.4, 11.0 1.55 d, 4.31
6
4240
ZHANG
C 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 OMe
OAc
1 29.8 18.4 35.9 37.6 62.3 73.7 95.9 60.2 53.1 37.0 68.6 28.4 29.1 29.6 223.0 57.3 69.1 27.9 66.6 69.1 58.7 170.7 169.7 21.6 20.6
R0~f.2
Table
2. 13CNMR
spectra
2
3
4
5
6
73.2 29.9 33.6 37.6 62.3 74.2 96.3 59.8 54.9 43.1 66.9 39.4 34.8 27.1 211.2 154.3 115.5 27.8 66.2 66.9
29.6 18.5 36.3 37.6 63.1 74.0 96.2 60.9 54.5 37.8 65.3 31.7 29.4 29.4 224.5 58.1 69.3 27.7 66.7 69.3 58.7
30.1 18.7 41.5 34.1 61.5 74.7 95.9 60.2 53.3 37.0 68.8 28.4 29.1 29.7 223.1 57.3 69.1 33.9 22.4 68.5 58.9
76.2 24.4 38.7 34.0 62.8 74.3 95.6 61.2 58.8 40.5 62.9 32.2 30.0 29.8 224.7 58.7 68.9 32.6 21.9 64.7 58.7
30.8 18.7 36.4 37.6 61.8 74.3 96.4 60.0 54.7 37.8 65.6 41.5 34.9 27.4 210.9 154.4 115.5 28.4 67.1 69.6
170.7 20.7
170.8 20.9
169.8 21.6
170.1 21.6
170.7 20.7
(base peak). (Found: C 65.47, H 8.04. C23H3407 requires: C 65.38, H 8.11.) Adenolin E (5). Needles, mp 213.5-215”, [a];!’ -82.9”; UV A:$“’ nm (6): 202 (2532); IR v,,, cn-‘: 3418,3266, 1733, 1715, 1235;MSm/z:438[M]+,420[M-H,0]+,406[M-MeOH]+, 378 [M-MeCO,H]+, 360 [378-H,O]+, 300, 257, 195, 161, 121, 105, 91, 85, 55, 43 (base peak). (Found: C 63.15, H 7.83. Cz3H3.,08 requires: C 63.00, H 7.82.) Longikaurin D (6). Needles, mp 225-227”, [a]Y - 150.0”; UV IZ/zH nm (E): 239 (7263); IR v,, cm-‘: 3510,3275, 3218, 1716, 1700,1636,1244; MS m/z: 406 [M] +, 388 [M -H,O] +, 364,346, 328, 297, 269, 203, 149, 121, 107, 95, 83, 55, 43 (base peak). (Found: C 65.46, H 7.45, C,,H,,O, requires: C 65.01, H 7.44.) Acknowledgement-The authors identification of plant material.
thank
PING et al.
Professor
Li Xiwen for
of compounds
l-6
REFERENCES
” 2’ 3,
4’ 5
’ 6,
Fujita, T., Takeda, Y. and Yang Shingu, T. (1981) Heterocycles 16, 227. Huang Hao, Zhang Hognjie and Sun Handong (1990) Phytochemistry 29, 259 1. Li Chunbao, Sun Handong and Zhou Jun. (1988) Acta Chimica Sinica 46, 657. Rance, T. M., Sorensen, 0. W., Bodenhansen, G., Wagner, G., Ernst, R. R. and Wiizhrich, K. (1983) Eiochem. Biophys. Res. Commun. 117,458. Shen Xiaoyu, Sun Handong, Isogai, A. and Suzuki, A. (1990) Acta Botanica Sinica 32, 711. Chen Yiping, Sun Handong and Lin Zhongwen (1990) Acta Botanica Sinica 32 292.