| abstract |
Bissteroidal compounds of general formula (I), in which R1 stands for hydrogen, alkyl, acyl, fluorine, and X1R5, where X1 stands for oxygen and sulfur and R5 can either be hydrogen, alkyl, aryl; R2 stands for hydrogen and alkyl; the stereochemistry of C-13, C-14 and C-17 may either be a or b; X stands for oxygen, hydroxyl, trifluormethylsulfonyloxy, or (R6)2P, where R6 can be aryl, alkyl and cycloalkyl; R3 stands for hydrogen, alkyl, aryl, trialkylsilyl, fluorine and X2R6, where X2 stands for oxygen and sulfur and R6 stands for hydrogen, trifluormethylsulfonyl, alkyl, cycloalkyl or aryl. R4 can either be a substituent in the 6 or 7 position of the steroid with the meaning of hydrogen, alkyl, aryl, fluorine, and X3R7, where X3 stands for oxygen, sulfur or trialkylsilyl and R7 stands for hydrogen, trifluormethylsulfonyl, alkyl or aryl, and the B-ring of the steroid contains none or two double bonds. Enantio- and Diastereomeric derivatives of compounds of general formula (I), metal complexes thereof and their use in enantioselective reactions. |