Acetylenic bond participation in biomimetic polyene cyclizations. Model studies directed toward the synthesis of 20-keto steroids. Synthesis of dl-progesterone and dl-.DELTA.4-androstene-3,17-dione
[EN] SYNTHESIS OF ENT-PROGESTERONE AND INTERMEDIATES THEREOF<br/>[FR] SYNTHÈSE DE L'ÉNANTIOMÈRE DE LA PROGESTÉRONE ET SES INTERMÉDIAIRES
申请人:PREVACUS INC
公开号:WO2016044558A1
公开(公告)日:2016-03-24
The present invention relates to the synthesis of ent-progesterone and intermediates thereof.
本发明涉及炔诺酮及其中间体的合成。
11-Substituted steroids and intermediates
申请人:The Board of Trustees of Leland Stanford Junior University
公开号:US04032579A1
公开(公告)日:1977-06-28
Precursor compounds are provided for use in the synthesis of 11-chalcogensubstituted steroids and nor-steroids, particularly 18-, 19- and A-nor-steroids. The compounds are acyclic or substituted polyenine with the olefinic groups having the proper geometry to provide the natural ring fusions upon cyclization. To initiate cyclization, a chalcogen atom is positioned in relation to a double bond, so that on protonation of the chalcogen atom, the resulting carbocation will interact with the double bond to form a pi bond if the cyclization initiator is carbocyclic and a sigma bond if the cyclization initiator is acyclic. Upon cyclization, it is found that the substituent at C-11 of the resulting steroid is in the alpha position. Various methods are provided for producing the cyclization precursor.
Olefinically unsaturated substituents at C-11 of steroid cyclization
申请人:The Board of Trustees of Leland Stanford Junior University
公开号:US04064185A1
公开(公告)日:1977-12-20
Compositions are provided as well as methods for preparing the compositions which serve as cyclization precursors for the preparation of C-11 alkenyl substituted steroids and nor-steroids. The alkenyl group may be converted after cyclization to a variety of heterosubstituents to provide heterofunctionalized C-11 steroids and nor-steroids. The compounds are provided having an initiator group, which has a chalcoxy atom in juxtaposition to a double bond, an olefinically unsaturated linking group and a terminating group which acts to from a carbocation which reacts with a nucleophile to provide a stable product. The C-11 substituent is found to provide upon cyclization the alpha-configuration, so that the subject compounds provide a direct route to the difficultly accessible alpha-C-11 substituted steroids, or, if desired, the alpha-configuration can be inverted to the beta-configuration.
申请人:The Board of Trustees of Leland Stanford Jr. University
公开号:US04129599A1
公开(公告)日:1978-12-12
Method is provided for cyclization of polyunsaturated substituted acylic or monocarbocyclic initiator group containing compound having an endocyclic double bond with a chalcogen atom in the allylic position of the initiator group and having at least two sites of unconjugated aliphatic unsaturation in the side chain substituent on the ring. The polyunsaturated compound is cyclized in the presence of a strong acid in a protic solvent which is inert to the acid, preferably a hydroxylic solvent. Mild temperatures and varying times are employed. The products are useful primarily as intermediates for naturally occurring and synthetic steroids. By appropriate substitution of the side chain, the steroidial products are provided with the substituent at C-11, which upon cyclization results in the alpha-configuration. By resolution of the intermediates prior to cyclization, optically active steroids can be obtained.