Two Androstane Derivatives; Least-Squares Analysis of the Cosine Invariants
The structures of 5α-androstan-3β-ol-17-one (C19H30O2) and 5β-androstane-3α, l7β-diol (C19H32O2) were solved via the least-squares analysis of the calculated cosine invariants, cos (ø1+ø2+ø3). Both these substances crystallize in space group P21 with two molecules in the unit cell. The computational procedure whereby phases were derived from the invariants is discussed in detail. The computed cosine invariants were compared with the observed values, and it was found that invariants for which the true value is relatively large are computed more accurately than invariants having smaller values.
KeywordsResi Sorting Diol Androstane Estriol
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