ASYMMETRIC-SYNTHESIS OF STEROIDAL TROGERS BASE ANALOGS - X-RAY MOLECULAR-STRUCTURE OF METHYL 3-ALPHA,12-ALPHA-(6H, 12H-5,11-METHANODIBENZO[B,F][1,5] DIAZOCINE-2,8-BISACETOXY)-5-BETA-CHOLAN-24-OATE
U. Maitra et al., ASYMMETRIC-SYNTHESIS OF STEROIDAL TROGERS BASE ANALOGS - X-RAY MOLECULAR-STRUCTURE OF METHYL 3-ALPHA,12-ALPHA-(6H, 12H-5,11-METHANODIBENZO[B,F][1,5] DIAZOCINE-2,8-BISACETOXY)-5-BETA-CHOLAN-24-OATE, Journal of the Chemical Society. Perkin transactions. I, (16), 1995, pp. 2049-2056
Cyclization of compound 5c in trifluoroacetic acid/hexamethylenetetram
ine produces Troger's base analogue 6c in 75% yield with 70% diastereo
selectivity.