Abstract
By condensing 3α, 21-dihydroxy-5β-pregnan-20-one, or its appropriate monoacetate, with methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-α- d-glucuronate in the Koenigs-Knorr reaction β- d-glucosiduronates 10 , 4 , and 7 were obtained as polyacetate methyl esters. Alkaline hydrolysis of these substances cleaved the ester groups and gave the corresponding steroidal glucosiduronic acids 12 , 6 and 8 . Upon treatment with diazomethane, these acids produced the equivalent methyl esters. The C-3, the C-21 and the C-3,21 glucosiduronates of 3α,21-dihydroxy-5β-pregnan-11,20-dione were prepared by previously reported methods and converted into the corresponding C-20 semicarbazones ( 14 , 20 and 26 ). With C-20 stabilized by the semicarbazone group against reduction, it was possible to reduce the 11-oxo function in these substances to an 11β-hydroxyl group; after removal of the semi-carbazone moiety from these products at pH 2.0, glucosiduronic acids 18 , 22 and 28 were obtained. The mass spectra of a representative group of the mono- and diglucosiduronic acids and esters were determined by utilizing fast atom bombardment and monitoring ions in both positive and negative modes of operation.
Published Version
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