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清香桂碱D和矮陀陀胺碱A,B的结构 总被引:9,自引:0,他引:9
本文报道从国产清香桂(Sarcococca ruscifolta)和金丝矮陀陀(Pachysandra axillaria)植物中分得的三个胺碱型新甾体生物碱清香桂碱 D 和矮陀陀胺碱 A、B 的化学结构,并首次归属了它们的~(13)C NMR 数据。 相似文献
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Reproductive structures and systematics of Buxaceae 总被引:3,自引:0,他引:3
MARIA VON BALTHAZAR PETER K. ENDRESS 《Botanical journal of the Linnean Society. Linnean Society of London》2002,140(3):193-228
Buxaceae belong to a grade of families near the base of eudicots. Flowers of these families are characterized by a variable number and arrangement of floral organs. In this study, the anthetic structure of the gynoecium and androecium of representatives of all genera of Buxaceae were comparatively studied, and observations on the flowering processes and pollination biology were made. Styloceras and Notobuxus were studied in detail for the first time. Various features of the morphological analysis support our earlier molecular phylogenetic study. Shared reproductive characters among Sarcococca , Pachysandra and Styloceras are the occurrence of two (rarely three) carpels, the lack of interstylar nectaries, a micropyle formed by both integuments, attractive stamens in male flowers, and fleshy fruits. In addition, Styloceras and Pachysandra share a secondary partition in the ovary. Notobuxus does not seem to be clearly distinct from Buxus . Both have a similar inflorescence and perianth structure; female flowers have three carpels, interstylar nectaries, micropyles formed by the inner integument, rudimentary arils, and they develop into capsular fruits; in male flowers stamens are sessile and the central pistillode is lacking in some species. Thus, it is questionable to justify a separation of Buxus and Notobuxus at genus level. The results further strongly support the placement of Buxaceae among basal eudicots. © The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 193–228. 相似文献
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In this paper, three new alkaloids, sarcorucinine D (1), and paehyaximine A, B (2, 3) were isolated from Sarcococca ruscifolia Stapf and Pachysandra axillaris Franch, respectively. The structures of sarcorucinine D (1) and pachyaximine A, B (2, 3) were elucidated to be 3β-hydroxyl-20α-dimethylamino-5α-pregnane (1); and 3β-methoxyl-20α-dimethylamino-pregne-5-ne (2); and 3β-methoxyl-16-hydroxyl-20α-dimethylaminopregne-5-ne (16-hydroxyl-pachyaxi- mine A) (3), respectively. 相似文献
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作者于1981—1983年随中国科学院青藏综合科学考察队赴横断山区考察,采集到不少莎草科植物标本。近年来、在承担《横断山区植物》一书莎草科的编著任务中,除鉴定了青藏队采集的该科标本外,还鉴定了我所标本馆收藏的该科部分标本,发现了一些新分类群,现在本文发表. 相似文献
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对国产黄杨科5 种植物作了分类学修订或补充: 将雀舌黄杨归入匙叶黄杨, 中间黄杨归入黄杨, 多毛板凳果归入板凳果, 双蕊野扇花归入羽脉野扇花; 恢复黄杨和尖叶黄杨的原学名;报道宜昌黄杨在湖南的新记录。 相似文献
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The bioassay-guided phytochemical investigation on Sarcococca hookeriana have resulted in the isolation of four new pregnane-type steriodal alkaloids: hookerianamide-D [(2'E,20S)-20-(N,N-formyl(methyl)amino)-3beta-(3',4'-dimethyl-2'-pentenamido)-5alpha-pregnane] (1), hookerianamide-E [(2'E,20S)-20-(N,N-dimethylamino)-3beta-(senecioylamino)-5alpha-pregn-14-en-2beta-O-acetate] (2), hookerianamide-F [(2'E,20S)-20-(N-methylamino)-3beta-(tigloylamino)-5alpha-pregn-2,14-dien-4-one] (3), and hookerianamide-G [(20S)-20-(N,N-dimethylamino)-3beta-(N-methylbenzamido)-5alpha-pregn-4beta-O-acetate] (4), along with five known alkaloids 5-9. Their structures were determined by spectroscopic analysis. These steroidal alkaloids and chemically derived derivatives of compound 5 have displayed varying degree of inhibitory activities against acetylcholinesterase and butyrylcholinesterase enzymes in a concentration-dependent fashion, with the IC(50) values ranging from 1.5 to 148.2 and 0.6 to 100.2 microM, respectively. 相似文献
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Khalid A Zaheer-ul-Haq Ghayur MN Feroz F Atta-ur-Rahman Gilani AH Choudhary MI 《The Journal of steroid biochemistry and molecular biology》2004,92(5):477-484
A new steroidal alkaloid, isosarcodine (1) along with four known bases, sarcorine (2), sarcodine (3), sarcocine (4) and alkaloid-C (5) were isolated from the MeOH extract of Sarcococca saligna. The structures of these alkaloids were identified by spectral data interpretation. These compounds were subjected to acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition studies, and were found to be noncompetitive inhibitors of AChE (Ki = 21.8, 90.3, 32.2, 16.0 and 50.0 μM, respectively) and uncompetitive or noncompetitive inhibitors of BChE (Ki = 8.3, 7.5, 15.6, 5.0 and 12.0 μM, respectively).
The compounds (2–5) also showed dose-dependent spasmolytic activity in the rabbit jejunum intestinal preparations and also relaxed the high K+ (80 mM)-induced contraction, indicative of a calcium channel-blocking mechanism.
Structure–activity relationship suggested that the nitrogen substituents at C-3 and/or C-20 of steroidal skeleton and the hydrophobic properties of the pregnane skeleton are the key structural features contributed to the inhibitory potency of these steroidal alkaloids against AChE and BChE. 相似文献
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Sarcococca vagans Stapf (Buxaceae) was distributed in Southern Yunnan, China. From the plant collected in Xishuangbanna,three new steroidal alkaloids named vaganines A,B and C( Ⅰ–Ⅲ )together with three known compounds were isolated and on the basis of spectral analyses and chemical evidence, the chemical structures of three new compounds were determined as 20α-dimethylamino-4β-acetoxyl-3β-senecioylamino-5α-pregnane (Ⅰ), 20α-dimethylamino-4β hydroxyl- 3-senecioylamino-△2(3)-pregnaene (Ⅱ), acetate of Ⅱ (Ⅲ); respectively. 相似文献
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国产黄杨科六种植物的考订 总被引:4,自引:0,他引:4
林祁 《热带亚热带植物学报》1999,7(1):31-33
对国产黄杨科6种植物作了修订或补充:将头花黄杨归入匙叶黄杨,平卧皱叶黄杨、越橘叶黄杨和矮生黄杨归入皱叶黄杨,汕头黄杨归入狭叶黄杨,东方野扇花归入长叶柄野扇花。报道了杨梅黄杨在湖北、江西和福建的新分布,皱叶黄杨在广西和福建的新分布,双蕊野扇花在贵州和广西的新分布。 相似文献
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