Studies on stereocontrolled epoxidations of bis-alicyclic alcohols in steroidal skeletons: preparation of eight diastereomerically pure epoxides from cholest-4-en-3β,6β-; -3β,6α-; -3α,6β- and -3α,6α-diols

Eight diastereomerically pure epoxides have been prepared from cholest-4-en-3β,6β; -3β,6α-; -3α,6β- and -3α,6α-diols via a combination of steric, protecting group and oxidant effects on stereocontrolled epoxidations of a bis-alicyclic alcohol system within the steroidal skeleton.     

3β-乙酰氧基-5α,6β-双羥基-6α-甲基-25D-螺甾的重排反应

C_6上有α-位甲基的甾体副肾皮激素不仅比可的松(cortisone)的疗效更强,而且无纳素保留的副作用。如在C_6上再加入一双键如△~6-6-甲基可的松,除6α-甲基副肾皮激素的作用外,还有利尿作用。3β-乙酰氧基-5α,6β-双羟基-6α-甲基-25D-螺甾(I)是合成△~6-6-甲基副肾皮激素的重要中间体。我们在用甲酸试行脱水反应时,希望获得△~6-     

6α-carboxy and 6α-carbamoyl,penicillins

Hemiacetal formation from 6α-formylpenicillins followed by oxidation has provided a series of esters of 6α-carboxypenicillins and the parent acid. Further derivatisation has afforded a 6α-carbamoylpenicillin.     

24-亚甲基-胆甾烷-3β,5α,6β-三醇的合成

豆甾醇;24-亚甲基-胆甾烷-3β;5α;6β-三醇的合成     

3β-乙酰氧基-5β,6β-环氧-6α-甲基-25-D螺甾与三氟化硼的反应

3β-乙酰氧基-5β,6β-环氧-6α-甲基-25D螺甾(Ⅲ)在与三氟化硼反应时按双竪鍵破环規律生成5α-氟-6β-羟基-6α-甲基化合物(Ⅳ),产物經变为已知体(Ⅴ)証明其結构与构型。     

Ab Initio Study of Prednisolone, 6α-Fluoroprednisolone, 9α-Fluoroprednisolone,and 6α,9α-Difluoroprednisolone

A theoretical study of prednisolone, 6-fluoroprednisolone, 9-fluoroprednisolone, and 6,9-difluoroprednisolone has been performed at the ab initio HF/6-31G, MP2/6-31G, and B3LYP/6-31G levels. Structural information and the electronic features of prednisolone and its derivatives and the synergistic effect of 6,9-difluoroprednisolone was examined. Contrary to the AM1 and MNDO results, we found 9-fluoroprednisolone is more stable than the 6-fluoroprednisolone. The increased corticosteroid activity of the 6,9-difluoroprednisolone is most likely due to electronic effects, mainly related to the receptor binding.     

SYNTHESIS OF 2α,3α-DIHYDROXY-Δ4,7-6-KETOSTEROIDS, STRUCTURAL ANALOGS OF DIAULUSTEROLS A AND B

We studied various methods for synthesizing 2,3-dihydroxy- ^4,7 -6-ketosteroids, which are structural analogs of the ecdysteroids diaulusterols A and B.     

Synthesis of 3β,6α-dihydroxy-5α-cholan-23-one

Evidence for the presence of 3β,6α-dihydroxy-5α-chol-9(11)-en-23-one in the aglycone mixture from the starfish Marthasterias glacialis is provided by the synthesis of 3β,6α-dihydroxy-5α-cholan-23-one (19) and its identification in the hydrogenated aglycone mixture. The side-chain is constructed from the 23,24-dinorcholanol (13) by reaction of the 22-tosylate (16) with the acetylide anion, followed by hydration of the resulting 23-yne (17).     

Synthesis of 6-chloronicotinates of steroidal 3β,5α,6β-triols and 3β,5-dihydroxy-6-ketones

New esters of 3β,5α,6β-trihydroxysteroids and 3β,5-dihydroxy-6-ketosteroids containing 6-chloropyridine groups characteristic of the alkaloid epibatidine were synthesized by acylation with 6-chloronicotinoylchloride. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 175-179, March-April, 2009.     

Synthesis of (24R)-3β,5,14α-trihydroxy-5α-stigmast-7-en-6-one 3-benzoate

An ecdysteroid analog has been synthesized from -sitosterol.Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus', 220141, Belarus', Minsk, ul. Akad. Kuprevich, 5/2. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 488–491, July–August, 1999.     

Reaction of 3β-chloro-5α,6α-epoxysteroids with trifluoroacetic acid

It has been established that on the interaction of the 5,6-epoxysteroids (1a–c) with trifluoroacetic acid in chloroform the 6-trifluoroacetates of the 5,6-diols (2a–c) are formed in high yield. The alkaline hydrolysis of the trifluoroacetates (2a–c) leads to the corresponding diols (3a–c).Institute of Bioorganic Chemistry, Belarus' National Academy of Sciences, 220141, Belarus', Minsk, ul. Akad. Kuprevicha, 5/2. Translated from Khimiya prirodnykh Soedinenii, No. 2, pp. 201–204, March–April, 1999.     

25,26,27-三失碳-B-高-7-氧-6-酮-5α-胆甾-3α,24-二醇的合成

本文报道以3α-羟基-6-羰基-5α-胆烷酸甲酯(3)为原料经六步反应合成了油菜甾醇类似物25,26,27-三失碳-B-高-7-氧-6-酮-5α-胆甾-3α,24-二醇(9a).总产率14%.9a的促进植物生长作用是24-表油菜甾醇内酯的60%.     

6α-甲基-17α-乙酰氧基黄体酮的合成

甾体激素往往因分子中在 C_6的α-位置加入一甲基而增强其疗效,例如6α-甲基可的松及6α-甲基可的唑(Ⅰ)均比其母体的功效大得多,黄体酮在 C_(17)上加入一乙酰氧基可使其疗效较为持久,若再在 C_6-α位置上加入甲基则不但疗效比母体大五、六十倍,并可内服,而黄体酮则只能注射,此物(Ⅺ)的已知合成方法中,似以 Babcock 等的方法较为简便。其法是用17α-羟基黄体酮(Ⅱ)为原料,即先作成 A 环上应有的不饱和酮簇,然后再加入6α-甲基,最后引入17α-乙酰氧基得Ⅺ。     

(3S,6S)-及(3S,6R)-3-苄氧甲基-6-甲基-吗啉-2,5-二酮的 制备及其晶体结构

以2-溴丙酸和N-叔丁氧羰基-O-苄基-L-丝氨酸为起始试剂首先制得N-(2-溴丙基)-O-苄基-L-丝氨酸(BPBS), 在N,N-二甲基甲酰胺(DMF)/三乙胺(Et3N)溶剂中80 ℃经9 h后BPBS发生分子内环化反应生成(3S,6S)-3-苄氧甲基-6-甲 基-吗啉-2,5-二酮[(3S,6S)-BMMD]及(3S,6R)-BMMD共存体, 产率70%. 将所制得的共存体以乙酸乙酯为重结晶溶剂, 采用微分重结晶法, 经4次“溶解-部分重结晶”操作循环制得两种纯光学构型的(3S,6S)-BMMD和(3S,6R)-BMMD. 将两种光学纯双手性中心的BMMD分别溶于乙酸乙酯, 室温下培养得(3S,6S)-BMMD和(3S,6R)-BMMD的单晶体, 以X射线衍射法测定上述两种BMMD的分子结构.     

(-)-（3S, 6R）-3, 6-羟基-10-甲基十一酸及其三聚体的全合成

以廉价易得的异戊基溴为起始原料,以烯丙基二异松莰烷基硼烷参与的不对称烯丙基化反应和Yamaguchi酯化反应为关键步骤,实现了对(-)-(3S,6R)-3,6-二羟基-10-甲基十一酸(总收率27.5％)及其三聚体(总收率24.5％)的不对称全合成。     

甾体植物生长促进剂合成的研究 Ⅶ.从猪去氧胆酸合成2α,3α-双羟基-7-氧杂-6-酮-23,24-双失碳-B-高碳-5α-胆甾酸和2α,3α-双羟基-7-氧杂-6-酮-24-失碳-B-高碳-5α-胆甾酸

从猪去氧胆酸(5)经一系列化学反应制得两个油菜甾醇内酯类似物,2和6.     

甾体植物生长促进剂合成的研究VII: 从猪去氧胆酸合成Zα, 3α-双羟基-7-氧杂-6-酮-23,24-双失碳-B-高碳-5α-胆甾酸和2α, 3α-双羟基-7-氧杂-6-酮-24-失碳-B-高碳-5α-胆甾醇

从猪去氧胆酸经一系列化学反应制得两个油菜甾醇内酯类似物.2α, 3α-双羟基-7-氧-6-酮-23,24,-双失碳B-高碳-5α-胆烷酸和2α, 3α-双羟基-6-酮-24-失碳-B-高-7-氧-5α-胆烷酸.     

3, 6-二芳基-5, 6-二氢均三唑[3, 4-b][1, 3, 4]噻二唑的合成 及生物活性

研究了在L-(+)-酒石酸存在下3-芳基-4-氨基-5-巯基-1,2,4-均三唑与醛的Mannich反应及分子内的加成反应,合成了15个新的手性稠杂环化合物3,6-二芳基-5,6-二氢均三唑[3,4-b][1,3,4]噻二唑,利用IR、^1HNMR和MS确证了其结构,并测试了部分化合物的生物活性。     

3, 6-二取代-均三唑并[3, 4-b]-1, 3, 4-噻二唑的合成

研究了2-苯基-1, 2, 3-三唑-4-羧酸(1)与3-烷基/芳基-4-氨基-5-巯基-1, 2, 4-三唑(2a～o)在POCl~3催化下, 脱水缩合得到15个新的3-烷基/芳基-6-(2'-苯基-1', 2', 3'-三唑-4'-基)均三唑并[3,4-b]-1, 3, 4-噻二唑类化合物(3a～o)。     

Synthesis of 2β, 3β, 14α-trihydroxy-Δ4,7-6-ketosteroids and their derivatives

A scheme using -sitosterol as an example for synthesizing 2, 3, 14-trihydroxy-^4,7-6-ketosteroids and their derivatives from 3-hydroxy-⁵-steroids was developed.Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus, 220141, Belarus, Minsk, ul, akad. Kuprevicha, 5/2. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 244–248, May–June, 2000.