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Some 20-p-tolyl analogs of 20α-hydroxycholesterol and cholesterol have been synthesized and tested as precursors of pregnenolone. As in the previously synthesized t-butyl analog, (20R)-20-t-butyl-5-pregnene-3β,20-diol, C-22 in these synthetic compounds is completely substituted and therefore unavailable for biological hydroxylation (1). (20R)-20-(p-Tolyl)-5-pregnene-3β,20-diol, 1, when incubated with an acetone powder preparation of bovine adrenal mitochondria forms pregnenolone and progesterone in good yield (more than 23%). (20S)-20-(p-Tolyl)-5-pregnen-3β-ol, 2, prepared by Raney nickel hydrogenation of 1, when incubated in a similar fashion yields 1 in large quantity in addition to small amounts of pregnenolone and progesterone. This is the first reported instance of substantial in vitro 20α-hydroxylation of a 22-desoxy substrate, natural or artificial. The styrene 20-(p-tolyl)-5,20-pregnadien-3β-ol, 3, made by dehydration of 1, is not a substrate for side chain cleavage. The results support the previously advanced hypothesis that the true intermediates in the side chain cleavage of cholesterol are reactive complexes of a metalloenzyme and oxygenated steroidal species, and not free hydroxylated compounds. Two reaction mechanisms consistent with these findings are proposed.

Anomalous drainage of a single left superior vena cava into the left atrium is rare, and correction presents a technical problem. This report describes a patient with absent right superior vena cava, a persistent large left superior vena cava draining to the left atrium, and an intact interatrial septum. Surgical correction was accomplished by removing the entire septum and placing a cloth baffle to cover the orifices of the pulmonary veins and mitral valve, thus partitioning pulmonary venous blood into the left ventricle. This technique of septal excision and replacement is applicable to other complicated anomalies involving the systemic and pulmonary venous channels and their relationship to the two atria. The surgical management of related anomalies of the superior vena cava is also discussed.