Sol J. Daum

Synthesis and androgen receptor affisity of steroidal methylsulfonylforans and a menthylsulfonylthiophene

Abstract Syntheses of the unsubstituted steroidal [3,2-b]furan ( 3a ), thiophene ( 3b ) and [2,3-b]furan ( 24 ) are described. Lithiation of the THP ethers 18a and 18b followed by the reaction with methyl disulfide and deprotection gave the 5′-methylsulfide derivatives 19a and 19b . Oxidation of the sulfides and ethynylation provided the compounds 2a and 2b . Swern oxidation of the [2,3-b]furan 24 with DMSO/TFAA/diisopropylethylamine resulted in oxidation to the 17-ketone and introduction of a 5′-methylthio group to give 25 . Ethynylation at C-17 followed by oxidation of the sulfide group provided the product 27 . 5′-Methylsulfonyl[3,2-b]furanosteroid 2a bound to the rat ventral prostate androgen receptor. However, the corresponding thiophene 2b and the [2,3-b]furan 27 lacked affinity for the receptor.

An efficient method for the synthesis of 4-benzoylthioazetidinones

Abstract The kinetically-controlled S-benzoylation of secondary thioformamides in the presence of triethylamine at low temperature provided S-benzoylthioimidates 6 . Without isolation, these unstable intermediates were utilized in the ketene-imine cycloaddition reaction with phthalimidoacetyl chloride/triethylamine to give 4-benzoylthioazetidinones 7 in yields up to 95%.