This invention relates to compounds of the formula ##STR1## wherein R.sub.1 represents lower alkyl, phenyl, or phenyl lower alkyl; R.sub.2 represents lower alkyl; and R.sub.5 represents lower alkyl. These compounds are useful as intermediates in the preparation of collagenase inhibiting compounds which are useful in the treatment of arthritis and are of the formula ##STR2## wherein R.sub.1 represents lower alkyl, phenyl or phenyl lower alkyl; R.sub.2 and R.sub.4 represent lower alkyl; and R.sub.3 represents lower alkyl, benzyloxyalkyl, alkoxybenzyl or benzyloxybenzyl wherein the oxyalkyl or alkoxy moiety contain 1 to 6 carbon atoms; and a, b, and c represent chiral centers with optional R or S stereochemistry.
本发明涉及式(I)化合物,其中R.sub.1代表较低的烷基、苯基或苯基较低的烷基;R.sub.2代表较低的烷基;R.sub.5代表较低的烷基。这些化合物在制备抑制
胶原酶的化合物中作为中间体很有用,这些化合物在治疗关节炎方面很有用,其式为(II),其中R.sub.1代表较低的烷基、苯基或苯基较低的烷基;R.sub.2和R.sub.4代表较低的烷基;R.sub.3代表较低的烷基、苄氧基烷基、烷氧基苯甲基或苄氧基苯甲基,其中oxyalkyl或alkoxy基团含有1到6个碳原子;a、b和c代表手性中心,可选R或S立体
化学。