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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Synthesis of 6,19-cyclopregnanes. Constrained analogues of steroid hormones
Pablo H Di Chenna1, Adriana S Veleiro, Juan M Sonego
1Departamento de Química Orgánica and UMYMFOR (CONICET-FCEN), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina.
Abstract:
A procedure for the synthesis of 6,19-cyclopregnanes is described involving an intramolecular alkylation reaction of Delta(4)-3-keto steroids with a 19-mesylate in the presence of KOH in isopropanol. Three 6,19-cyclopregnanes were prepared (4, 5 ,9); in the rat, 6,19-cycloprogesterone (4) and its 21-hydroxy derivative 5 displaced [3H]-dexamethasone from glucocorticoid receptors, the former compound being more active. Both compounds did not compete with [3H]-aldosterone for kidney mineralocorticoid receptors nor with [3H]-R5020 for uterus progesterone receptors.
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