C= K band (at 1640 c1n-l in liquid film or in CHC13) and the SH triplet [6 1.41 in CDC1,; 1.95 in (CD&SO] in its n. ii1. r. spectrum. The nmr spectrum of the cyclic salt in (CD8) SO showed four signals (in ppm from TA'IS), a sharp singlet at 1.80, two triplets at 2.96 and 4.18 (J= 6.6 cPs), and a relatively sharp but broad band at 9.38 in the ratio of 3: 1: 1: 1, corresponding to the (CHs) &, CHzS, CH20, and NH2 resonances; the signal for an SH proton was absent. ...