Abstract
The reaction of mercaptoacetamide or cysteine with trans-π-oxocamphor, a respiratory and cardiac stimulant, was studied together with comparative examination with some other aliphatic and aromatic aldehydes. trans-π-Oxocamphor, 10-oxocamphor, formaldehyde, and acetaldehyde mixed with mercaptoacetamide in their alcoholic solution gave 2-substituted thiazolidone derivatives (formula C) under dehydrative ring formation. On the other hand, the aromatic aldehydes, benzaldehyde, p-nitrobenzaldehyde, and p-dimethylaminobenzaldehyde, under the same mild conditions, formed only hemimercaptal compounds (formula A), which were however transformed into the corresponding thiazolidones on treatment with anhydrous zinc chloride. 2-(trans-π-Apocamphoryl)-4-carboxythiazolidine (XI) obtained from d-trans-π-oxocamphor and l-cysteine considerably dissociates in the aqueous solution into its components, and no noticeable formation of the addition product was observed in the solution of 2×10-4 M of both components (Fig. 2).
