20,21-Aziridine Steroids: Reaction of Derivatives of the Oximes of 5-Pregnen-
20-one, 9 /3,10a-5-Pregnen-20-one and 9 /3,lOa-5,7-Pregnadiene-2O-one with Lithium Aluminium Hydride, and of 3 /3-Hydroxy-5-pregnen-ZO-one Oxime with GrignardReagents. -Suwznzary. Reduction of 3P-hydroxy-5-pregnen-20-one oximc (2) with LiAlH4 in tctrahydrofuran yielded 20P-amino-5-pregnen-3p-01 (I), 20u-amino-5-pregncn-3~-01 (3), ZOP, 21imino-5-pregnen-3p-01 (6) and 20a, 21-imino-5-pregnen-3j?-ol (9). The aziridines 6 and 9 were separated via the acetyl derivatives 7 and 10. The reaction of 6 and 9 with CS2 gave 5-(3P-hydroxy-5-androstcn-17~-yl)-thiazolidinc-2-thione (8). Trcatment of the 20-oximes 12 and 15 of the corresponding 9P, lOcc(retro)-pregnane derivatives with LiAlH4 gave the aziridines 13 and 16, respectively. Their deaniination led to the diene 14 and triene 17, respectively. Reduction of isobutyl methyl ketone-oxime with LiAlH4 in tctrahydrofuran yielded 2-amino-4-methyl-pentane (19) as main product, 1,2-imino-4-methyl-pentane (22) as second product and the epimeric 2,3-imino-4-methyl-pentanes 20 and 21 as minor products. -3P-Hydroxy-5-pregnen-2O-one oximc (2) was transformed by methylmagnesium iodide in toluene to 20u, 21-irnino-20-methyl-5pregnen-3P-01 (23) and ZOP, Zl-irnino-20-methyl-5-pregnen-3/3-01 (26). Acetylation of these aziridines was accompanied by elimination reactions leading to 3P-acetoxy-20-methylidene-21-S-acetylamino-5-pregncnc (30) and 3~-acetoxy-20-methyl-2l-N-acetylamino-5,17-pregnadienc (32). The reaction of oxime 2 with ethylmagnesium bromide in toluene gave 20a, 21-imino-20rthyl-5-prcgnen-3P-01 (24) and 20,B,21-irnino-20-ethyl-5-pregnen-3P-o1 (27). Acetylation of 24 and 27 led to 3~-acetoxy-20-ethylidene-2l-N-acetylamino-5-pregnene (31), 3p-acetoxy-20-ethyl-21-N-acetylamino-5,17-pregnadiene (33) and 3P, 20-diacetoxy-20-ethyl-21-X-acetylamino-5pregnenc (37). IVith phcnylniagnesium bromide in toluene the oxime 2 was transformed to 2Oa,21imino-20-phenyl-5-pregnen-3~-ol (25) and ZOP, 21-imino-20-phenyl-5-pregncn-3P-01 (28). Acetylation of 25 and 28 yielded 3P-acetoxy-20-phenyl-2l-N-acetylamino-5,17-pregnadiene (34) and 3 /3,20-diacetoxy-20-phenyl-2l-N-acetJilamino-5-pregnene (39). LiAEf4-rcduction of 39 gave 3 p , 20-dihydroxy-20-phenyl-21-N-ethylamino-5-pregnene (41). --The 20,21-aziridines are stable to LiAIH4. Consequently they are no intermediates in the formation of the 20-amino derivatives obtained from the oximc 2. 1 . Einleitung. -Die Keduktion von Oximen mit LiAlH4 fuhrt gewohnlich zu den entsprechenden primaren Aminen, wobei die Ausbeuten betrachtlich variieren !1]. Es ist bekannt, dass die Reduktion von Arylketoximen [Z] und gespannten alicyclischen Ketoximen r3] neben den primaren Aminen als Folge einer elektrophilen HELVETICA CHIMICA ACTA -Vol. 59, Fasc. 5 (1976) -Nr. 193 1851 Aluminiumhydrid-katalysierten Beckman7z-Umlagerung und anschliessender Reduktion auch sekundare Amine [4] liefert. Im Jahre 1965 berichteten Kitahonoki et al. [5] und Freeman [6] erstmals, dass gewisse Ketoxime durch L...
