Title: Pregnenolone
CAS Registry Number: 145-13-1
CAS Name: (3b)-3-Hydroxypregn-5-en-20-one
Synonyms: D5-pregnen-3b-ol-20-one; 17b-(1-ketoethyl)-D5-androsten-3b-ol
Molecular Formula: C21H32O2
Molecular Weight: 316.48
Percent Composition: C 79.70%, H 10.19%, O 10.11%
Literature References: Prepn from stigmasterol: Butenandt
et al., Ber. 67, 1611 (1934); Butenandt, Fleischer,
Ber. 70, 96 (1937); from androstenolone: H. Butenandt, J. Schmidt-thome,
Ber. 72, 182 (1939); S. Danishefsky
et al., J. Org. Chem. 40, 1989 (1975); from D5-3-acetoxyetiocholenic acid chloride: Wettstein,
Helv. Chim. Acta 23, 1373 (1940); from diosgenin: Marker, Krueger,
J. Am. Chem. Soc. 62, 3349 (1940); Marker
et al., ibid. 69, 2173 (1947); from nologenin:
eidem, ibid. 2395; by treating a 21-halo-D5-pregnen-3-ol-20-one with a reducing agent:
CH 215139 (1941),
C.A. 42, 3144 (1948). Crystal structure: J. Bordner
et al., Cryst. Struct. Commun. 7, 513 (1978).
Properties: Needles from dil alc, mp 193°. [a]D20 +28° (alc). Very sparingly sol in water. Soly (g/100 ml of soln): carbon tetrachloride 0.5; petr ether 0.1; ethyl acetate 1.1; acetone 0.6; chloroform 17.0; ethanol 1.9; benzene 0.9; isopropanol 1.5. Soly (g/100 ml of solvent): propylene glycol 0.1; dioxane 3.1; benzyl alcohol 8.1. On refluxing with methyl alcohol yields the 17-isopregnenolone, mp 172-173°, [a]D20 -140.5° (alcohol).
Melting point: mp 193°; mp 172-173°
Optical Rotation: [a]D20 +28° (alc); [a]D20 -140.5° (alcohol)
Derivative Type: Acetate
Molecular Formula: C23H34O3
Molecular Weight: 358.51
Percent Composition: C 77.05%, H 9.56%, O 13.39%
Properties: Needles from alcohol, mp 149-151°. [a]D20 +22° (alcohol). Soly (g/100 ml of soln): carbon tetrachloride 5.0; petr ether 1.0; ethyl acetate 7.9; acetone 2.7; chloroform 55.0; ethanol 2.5; benzene 26.0; isopropanol 2.0. Soly (g/100 ml of solvent): propylene glycol 0.1; dioxane 20.2; benzyl alcohol 11.1; benzyl benzoate 9.1.
Melting point: mp 149-151°
Optical Rotation: [a]D20 +22° (alcohol)
Derivative Type: Methyl ether
CAS Registry Number: 511-26-2
Molecular Formula: C22H34O2
Molecular Weight: 330.50
Percent Composition: C 79.95%, H 10.37%, O 9.68%
Properties: Crystals from abs or dil methanol, mp 123.5°. [a]D18 +18° (c = 1.085 in chloroform).
Melting point: mp 123.5°
Optical Rotation: [a]D18 +18° (c = 1.085 in chloroform)
