[Molecular and crystallographic structure of D-11-aza-19-nortestosterone].

Crystal and molecular structure of D-11-aza-19-nortestosterone monohydrate C17H25NO2.H2O (a 8,288(2), b 12,433(2), c 7,570(2) A, beta 90,25(1) degrees; space group P2(1), R 8.3%) has been determined by X-ray analysis. Its comparison with the molecular structure of D-19-nortestosterone showed that the decrease in the hormonal activity upon 11-aza-substitution may be due to difference in chemical properties of imino and methylene groups.