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The concept of C-derivatization of amino acids via ß-and -chloro amino acids, obtained by selective free-radical chlorination in strong acid solution, is now extended to the -chlorination of an amino acid and in turn to the first synthesis of the optically active isomers of 3-methylproline. The exceedingly convenient synthesis does not affect the two asymmetric centers of the isoleucines employed as starting material; therefore it delivers the isomeric 3-methylprolines in optically pure form directly, without resolution. Moreover it concurrently establishes the absolute configuration of each of the four isomers. The J¡,¡ proton coupling values of the cis-trans isomers are practically identical.(10) Authors thank Mr. R. H. Redfield of these laboratories for performing several amino acid analyses.(11)

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Photofluorination with Fluoroxytrifluoromethane, a General Method for the Synthesis of Organic Fluorine Compounds. Direct Fluorination of Bioactive Molecules

Polarisation by cation formation (e.g., by protonation or by oxocarbonium ion formation) exerts a distinct and systematic effect on the selectivity of radical chlorination of aliphatic acids, amines, and alcohols. A qualitative correlation is demonstrated between the magnitude of deshielding of a given proton (as expressed by the downfield shift in the l H n.m.r. spectrum) and its '* deactivation '* as indicated by diminished rate of its abstraction by chlorine atoms. A convenient method is described for the preparation of new and known aliphatic mono-and polychloro-amines. New Jersey, U.S.A. * This reactor was designed and built with the valuable cooperation of Mr. R. Geiger of our machine shop.

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Benzolactam Growth Hormone Secretagogues: Replacement of the C-3 Amide Bond in L-692,429.-General benzolactams are created as potential new nonpeptidyl growth-hormone secretagogues on the basis of the known L-692429. It can be shown that the substitution of the C-3 amide bond by an urea moiety results in the formation of compounds like (IV), which have equal activity compared with the parent compound. -(OK, H. O.; SZUMILOSKI, J. L.; DOLDOURAS, G. A.; SCHOEN, W. R.; CHENG, K.; CHAN, W. W.-S.; BUTLER, B. S.; SMITH, R. G.; FISHER, M. H.; WYVRATT, M.