ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
20, 21-Aziridine Steroids: Reaction of Derivatives of the Oximes of 5-Pregnen-20-one, 9β, 10α-5-Pregnen-20-one and 9β, 10α-5,7-Pregnadiene-20-one with Lithium Aluminium Hydride, and of 3β-Hydroxy-5-pregnen-20-one Oxime with Grignard Reagents.Reduction of 3β-hydroxy-5-pregnen-20-one oxime (2) with LiAlH4 in tetrahydrofuran yielded 20α-amino-5-pregnen-3β-ol (1), 20β-amino-5-pregnen-3β-ol (3), 20β, 21-imino-5-pregnen-3β-ol (6) and 20β, 21-imino-5-pregnen-3β-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-(3β-hydroxy-5-androsten-17β-yl)-thiazolidine-2-thione (8). Treatment of the 20-oximes 12 and 15 of the corresponding 9β,10α(retro)-pregnane derivatives with LiAlH4 gave the aziridines 13 and 16, respectively. Their deamination led to the diene 14 and triene 17, respectively. Reduction of isobutyl methyl ketone-oxime with LiAlH4 in tetrahydrofuran 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. - 3β-Hydroxy-5-pregnen-20-one oxime (2) was transformed by methylmagnesium iodide in toluene to 20α, 21-imino-20-methyl-5-pregnen-3β-ol (23) and 20β, 21-imino-20-methyl-5-pregnen-3β-ol (26). Acetylation of these aziridines was accompanied by elimination reactions leading to 3β-acetoxy-20-methylidene-21-N-acetylamino-5-pregnene (30) and 3β-acetoxy-20-methyl-21-N-acetylamino-5,17-pregnadiene (32). The reaction of oxime 2 with ethylmagnesium bromide in toluene gave 20α, 21-imino-20-ethyl-5-pregnen-3β-ol (24) and 20α,21-imino-20-ethyl-5-pregnen-3β-ol (27). Acetylation of 24 and 27 led to 3β-acetoxy-20-ethylidene-21-N-acetylamino-5-pregnene (31), 3β-acetoxy-20-ethyl-21-N-acetylamino-5,17-pregnadiene 33 and 3β, 20-diacetoxy-20-ethyl-21-N-acetylamino-5-pregnene (37). With phenylmagnesium bromide in toluene the oxime 2 was transformed to 20β, 21-imino-20-phenyl-5-pregnen-3β-ol (25) and 20β,21-imino-20-phenyl-5-pregnen-3β-ol (28). Acetylation of 25 and 28 yielded 3β-acetoxy-20-phenyl-21-N-acetylamino-5, 17-pregnadiene (34) and 3β,20-diacetoxy-20-phenyl-21-N-acetylamino-5-pregnene (39). LiAlH4-reduction of 39 gave 3β, 20-dihydroxy-20-phenyl-21-N-ethylamino-5-pregnene (41). - The 20, 21-aziridines are stable to LiAlH4. Consequently they are no intermediates in the formation of the 20-amino derivatives obtained from the oxime 2.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19760590542
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