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SummaryResolution of racemic cis-3-(2-aminophenylthio)-2-hydroxy-3-(4-methoxypheny1)propionic acid (2) via the cinchonidine salt 3, and brucine salt 4, isolation of the calcium salts (+)-and (-)-5, as well as their cyclization to enantiomeric 1,s-benzothiazepines (+)-and (-)-1, are described. X-Ray single-crystal analysis reveals (2S, 3s) absolute configuration of (+)-1, and the existence of its 7-membered ring in a slightly twisted boat conformation in the solid state. M-absolute conformation in solution is assigned to (+)-1 on the basis of tentative comparison of CD data with those for the 1,4-benzodiazepine derivative (+)-8 of known absolute configuration.

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Structural properties of semiconductor alloys formed by solid solution between Ga2Se3 and α‐In2Se3 (R) are studied by X‐ray diffraction methods. In the whole range of concentrations four distinct phases are established stable at room temperature. Within 100% and approximately 75% (molar) of G2Se3 the existing phase is of zinc blende type as pure G2Se3 itself, showing some blurred diffraction lines. From approximately 88 to 55% of G2Se3 exists a phase designated as γ2, while from 55 up to 0.5% of G2Se3 a phase exists designated asγ1, both of them being similar to the high temperature, γ phase of In2Se3. From 2% to zero percent of G2Se3 exists a phase corresponding to the room temperature α(R) phase of In2Se3. The unit cell parameters continuously change with composition within the range of each phase, while at the transitions from one phase to the other “deduced” parameters (which correspond to one half of the face diagonal, and two thirds of body diagonal of the unit cell of zinc blende phase, respectively) change abruptly for little amounts. The system exhibits semiconducting properties in accordance with the high for bidden energy band of about 2 eV in all phases except that one corresponding to α‐In2Se3 (R), in which the conductivity is high. The other properties change from one phase to the other.

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