Stereochemical Aspects of Acid-Catalyzed Cyclopropane Ring-Opening Reactions. A Stereospecific Pathway to Crinosterol and Brassicasterol
作者:Robert W. Lang、Carl Djerassi
DOI:10.1002/hlca.19820650144
日期:1982.2.3
acetic acid leads stereospecifically to the naturally occurring crinosterol (4) and brassicasterol (6), respectively (Scheme 1). This isomerization can be viewed as a biomimetic model of an in vivo methylation process of the type already known in plant sterol metabolism (cf. cycloeucalenol obtusifoliol, 1 2). The synthetic application of this method provides a convenient labelling of sterol side chains
AKIHISA, TOSHIHIRO;TAMURA, TOSHITAKE;MATSUMOTO, TARO;KOKKE, W. C. M. C.;G+, J. CHEM. SOC. PERKIN TRANS. PT 1,(1990) N, C. 2213-2218
作者:AKIHISA, TOSHIHIRO、TAMURA, TOSHITAKE、MATSUMOTO, TARO、KOKKE, W. C. M. C.、G+
DOI:——
日期:——
Sterols of the unicellular algae Nematochrysopsis roscoffensis and Chrysotila lamellosa: isolation of (24E)-24-n-propylidenecholesterol and 24-n-propylcholesterol
作者:Daniel Raederstorff、Michel Rohmer
DOI:10.1016/0031-9422(84)83024-1
日期:1984.1
-propylidenecholest-5-en-3β-ol and 24- n -propylcholest-5-en-3β-ol, and (24 S )-24-ethylcholesta-5,22-dien- 3β-ol (stigmasterol) are the major sterols of Nematochrysopsisroscoffensis , a Chrysophyte of the Sarcinochrysidales order. This unique sterol composition is different from the sterol contents of other Chrysophytes and justifies the peculiar position of the Sarcinochrysidales, which are by some characteristics
摘要 两种稀有的 C 30 -甾醇,(24 E )-24-n-丙叉胆甾醇-5-en-3β-ol 和 24-n-丙基胆甾醇-5-en-3β-ol,和 (24 S )-24-乙基胆甾醇-5,22-dien-3β-ol(豆甾醇)是 Nematochrysopsis roscoffensis 的主要甾醇,它是结节藻目的金藻。这种独特的甾醇成分不同于其他金藻属的甾醇含量,并且证明了结节藻目的特殊位置是合理的,它们在形态学和生物学上与褐藻纲有关。(24 S )-24-methylcholesta-5,22-dien-3β-ol (24-epibrassicasterol) 作为 Chrysotila lamellosa 中的主要甾醇的存在与从其他 Prymnesiophyceae 获得的少数先前结果一致,尽管存在另一种主要甾醇,(24 R )-24-乙基胆甾醇-5,