The synthesis and biological activity of 4-[bis(2-chloroethyl)amino]-DL-, L, and D-phenylalanine amides and peptides

Abstract

The effects of temperature upon the Ar-perturbed K I 5802 A emission line (4p 2P3/2-7s 2S1/2) were measured with a Fabry-Perot interferometer. Low-pressure measurements were made between 443 and 760 K in a positive-column discharge. Computer analyses of the line shapes are based upon the semiclassical theory in the impact approximation, and experimental values of shift, width and near-wing asymmetry are obtained. Empirically, the width varies approximately as T o 37*0 O4 . On the basis of an assumed potential form I;,C,/R", the parameters c 6 and C8 are adequate to yield shift and width values in close agreement with experiment. The experimental parameter set is C, erg cm8 and C12=0. The importance of multitemperature measurements in reducing the ambiguity of c 6 and C8 is demonstrated. The existence of the theoretically predicted near-wing red asymmetry is shown, and the experimental value is in quantitative agreement with the calculated value. The calculated K(7s)/Ar potential does not agree with the Baylis-type pseudopotential in which the effective noble-gas atom radius ro corresponds to the ground state; however, a reduction in this radius yields moderately good agreement in the range R 2 19 A, which is shown to be the approximate validity range for the potential derived from these low-pressure measurements.-8.3 X lo-" erg cm', C8 2 8 . 9 x