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(13)C NMR spectroscopic data for 25 cephalosporin derivatives were assigned by combination of one- and two-dimensional experiments. The effect of the substitution at C-3, C-7 and C-4 acid group positions on the chemical shifts of the cephem nucleus is discussed.

New steroids derivatives having a chlorine and a bromine atom at 9α-position were obtained from a key intermediate 5α-9(11), 16-pregnadien-3β-ol-20-one acetate. These steroids have potential anabolic/androgenic activity.

Steroids U 0300Synthesis of 9α-Chloro-and Bromo-androstane Derivatives. -The synthesis of new 9α-halo-substituted steroids with potential anabolic/androgenic activity starting from epoxyandrostanol (I) is described. -(REYES, M.; ALVAREZ, Y. M.; FUENTE, A.; RUIZ*, J. A.; VELEZ-CASTRO, H.; J. Chem. Res. 2005, 7, 434-435; Cent. Quim. Farm., Habana, Cuba; Eng.) -R. Staver 49-165

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