Title:  Allopregnane-3a,20b-diol 
CAS Registry Number:  566-57-4 
CAS Name:  (3a,5a,20R)-Pregnane-3,20-diol 
Additional Names:  3a,20b-dihydroxy-5a-pregnane 
Molecular Formula:  C21H36O2 
Molecular Weight:  320.51 
Percent Composition:  C 78.69%, H 11.32%, O 9.98% 
Literature References:  Progesterone metabolite.  Prepn by hydrogenation of progesterone:  Marker, Lawson, J. Am. Chem. Soc. 61, 588 (1939); by catalytic hydrogenation of epiallopregnane-3-ol-20-one:  Marker, US 2231019 (1941 to Parke, Davis); by reduction of 5a-pregn-1-ene-3,20-dione with lithium aluminum hydride:  Schütt, Tamm, Helv. Chim. Acta 41, 1751 (1958). 
Properties:  Needles from acetone, mp 207-209°.  [a]D26 +12° (c = 1.132 in chloroform). 
Melting point:  mp 207-209° 
Optical Rotation:  [a]D26 +12° (c = 1.132 in chloroform)   |