Pregna-D'-pentaranes—a new class of active gestagenes

A novel electrogenerated base. Alkylation of methyl arylacetates at the .alpha.-methylene group

“…The residue was digested with hot hexane. The hexane was evaporated, leaving the crude urethane which was recrystallized from ethyl acetate-hexane mixed solvent to afford pure 10: 0.32 g, 57%; mp 133-134 °C; NMR (CDC13) 1.3 (s, 9 ), 1.51 (AB, Jab = 11 Hz, 1 H), 2.26 (AB, Jab = 11 Hz, 1 ), 2.9-3.7 (m, 7 ), 5.1 (s, 1 H); 13C NMR (CDClg) 28.34 (q), 35.29 (d), 37.67 (t), 42.22 (d), 43.57 (d), 45.30 (d), 45.96 (d), 47.31 (d) 58.14 (d), 67.14 (s), 80.20 (s), 128.36 (s), 154.14 (s); IR (KBr) 3330 (s), 2980 (m), 1660 (vs), 1550 (vs), 1360 (m), 1165 (s), 785 (m) cm"1; mass spectrum (70 eV), m/e (relative intensity) (no molecular ion), 235.15 (3.8), 189.05 (10.0), 115.05 (9.1), 66.05 (21.6), 64.95 (10.0), 59.05 (32.9), 57.05 (100.0), 56.05 (15.9), 55.05 (11.1), 53.05 (12.0), 50.95 (15.4), 43.95 (31.2), 43.05 (11.5), 41.05 (59.3).…”

Pregna-D′-pentaranes, progestins and antiprogestins: I. Separation of biological functions of steroid hormones

“…Its dehydrogenation with chloranil resulted in 6-dehydroanalogue (XXVII), whereas the dehydrogenation with 2,3-dichloro-5,6-dicyanoquinone (DDQ), in 1,2-dehydropentarane (XXV). The corresponding 6-demethyl-1,2-dehydropentarane (XXVI) was obtained in the same manner [10,[18][19][20].…”

“…Their purification, conversion into the mixture of corresponding tosylhydrazones, and hydride reduction resulted in a mixture of 3 β ,20-dihydroxy derivatives ( XXI ), transformed by standard methods to the target -pentarane ( VI ) [16,17] (Scheme 3.) [10] iii, iv iii, iv…”

“…The key stage in the synthesis of pregnane steroids with an additional six-membered D' ring in 16 α ,17 α -positions of steroid backbone served the ability of steroid 16-dehydro-20-ketones to enter the Diels-Alder reaction as dienophiles, we discovered [10,12]. The Lewis acid-catalyzed condensation of ( VII ) with 1,3-dienes proceeds at room temperature with the formation of the corresponding adducts ( XIa )-( XId ) in high yields (Scheme 2).…”

“…Pregna--pentarane ( II ), the first member of the series, was obtained by the standard cyclopropanation of 16-dehydropregnenolone acetate ( VII ) with diazomethane (through the stage of formation of the corresponding 16 α ,17 α -pyrazoline [10]), subsequent saponification of acetate and its oxidation to ∆ 4 -3 -ketone (Scheme 1). The reaction of photocycloaddition of acetylene to ( VII ) was used for the synthesis of pregna--pentarane ( III ) (Scheme 1).…”