On the Structure of Chlorpromazine

Coubeils and Pullman calculated, by means of a molecular orbital method, that the conformation of the side chain attached to the ring nitrogen depended on the folding of the phenothiazine ring systems along the S-N (ring) axis. These data were in agreement with available x-ray 

FIGURE 1. A model of chlorpromazine hydrochloride with gauche-trans side-chain conformation. (In this model one C proton and two Cy protons are equidistant from H-9, while the other Ca proton and the two Cp protons are equidistant from H-1.) 

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