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本文以吡啶铬酐盐酸盐(PCC)氧化剂,无水乙酸钠为缓冲试剂,在二氯甲烷中,室温,氧化两种甾-5-烯-3-醇,胆固醇(1a)和16,17α-环氧-孕甾-5-烯-3-醇(1b),经较长时间的反应,分别以84%和82%的收率制备了胆甾-4-烯-3,6-二酮和16,17α-环氧-孕甾-4-烯-3,6-二酮。这种方法简便易行,后处理方便,试剂易得,而且产品纯度较好,因此是一种具有一定实际价值的方法。 相似文献
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本文报道以猪去氧胆酸为原料,立体选择性地合成(SS2,23S)-香蒲甾醇,合成的关键步骤是用Li2Cu3(CH3)5立体专一地转化烯丙醇苯胺基甲酸酯10和13成为11和用OsO4-NMO在化合物16的不饱和侧链上立体选择性羟基化。 相似文献
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QingAnZHENG ChongRenYANG 《中国化学快报》2003,14(12):1261-1264
Two new C-22 steroidal lactone glycosides, named dracaenoside A and B were isolated from the methanol extract of the fresh stem of Dracaena cochinchinensis. Their structures were established as (20S)3β,14α,16β-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-α-L-rhamnopyranosyl (1→2)[ α-L-rhamnopyranosyl (l→4)]-β-D-glucopyranoside and (20S)3β, 14α,16β-trihydroxy pregn-5-ene-22-carboxylic acid (22,16)-lactone 3-O-α-L-rhamnopyranosyl (1→2)[β-D-glucopyranosyl(1→3)]-β-D-glucopyranoside by means of 2D NMR spectral and chemical methods. It is the first time that steroidal lactone glycosides were isolated from the genus Dracaena. 相似文献
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