Patent CA-1269364-A (CA)
Title: Substituted penem derivatives and process for their  preparation
Inventor: ALPEGIANI MARCO
IPC: C07D499/04
Filed: 1983-04-06
Granted: 1990-05-22
Abstract: ABSTRACT OF THE DISCLOSURE         This invention discloses a new process for the preparation of substituted penems, to penem compounds and to their preparation and use in pharmaceutical and veterinary  compositions.  The compounds are of the general formula (I)    (I) wherein R1 is hydrogen or an organic group;        R2 is hydrogen or a carboxy protecting group; and Y is (a) a group-S-Het wherein Het is an optionally substituted saturated or unsaturated heterocyclic ring containing at least one heteroatom selected from O,S and N;           (b) a formyloxy or a C2-C6 carboxylic acyloxy group with a substituted or unsubstituted acyl group;   (c) a 1-12 alkoxy or C1-12 alkylthio group which may be substituted or unsubstituted;           (d) an optionally substituted pyridyl group or (e) azido; and the pharmaceutical and veterinary acceptable salts thereof.  These compounds exhibit good antibacterial activity against both gram-positive and  gram-negative bacteria and are used in the treatment of bacterial infections.  The toxicity of the compounds is very low and they may be administered using many different methods,  The compounds of the general formula (I) Abstract continued...   are prepared by reacting a compound of the formula (II)             (II) wherein R1 and R2 are defined hereinbefore and L is chlorine, bromine or a free or an activated hydroxy group with a compound of the general formula (III) Y-H          (III) wherein Y is as defined hereinbefore,or a salt thereof, or a reactive derivative thereof.  Disclosure is also made of new compounds of the general formula (Ia)                (Ia) wherein R'1 is a C1-C6 alkyl group substituted by a free or protected hydroxy;       R2 is hydrogen or a carboxy protecting group; and Y' is: 1)  an optionally substituted pyridyl group; or 2)  a group -S-alk-NH2 wherein Alk represents a C1-C3 alkylene; or 3)  a group -S-Het' wherein Het' represents: a)  1,3,4-thiadiazolyl either unsubstituted or substituted by a substituent chosen from (a') C2-C6 alkyl; (b') C1-C3 alkyl substituted by an optionally salified carboxy group;             Abstract continued....           (c') an optionally salified carboxymethylthio group, and (d') a group    wherein each of R' and R" is, independently, hydrogen or C1-C3 alkyl; b)  1,2,3-thiadiazolyl optionally substituted by a C1-C6 alkyl group; c)  1,2,3-triazolyl substituted by a C1-C6 alkyl group; d)  1,2,4-triazolyl optionally substituted by a group    wherein R' and R" are as defined above; e) 1,3,4-triazolyl optionally substituted by a C1-C6 alkyl group; f)  imidazolyl optionally substituted by a C1-C6 alkyl group; g)  thiazolyl optionally substituted by one or more substituents chosen from (a')   wherein R' and R" are as defined above;            (b') unsubstituted C1-C6 alkyl; and (c') C1-C3 alkyl substituted by an optionally salified carboxy group; h)  tetrazolyl optionally substituted by (a') unsubstituted C1-C6 alkyl, or (b') C1-C3 alkyl substituted by a substituent chosen from (i) optionally salified carboxy, (ii) optionally salified sulpho or sulfoamino, (iii) cyano, (iv) carbamoyl, (v)   Abstract continued....   wherein R' and R" are as defined above, and (vi) tetrazolyl; i)  pyrazinyl substituted by a C1-C6 alkyl or C1-C6 alkoxy group; l)  5-oxo-6-hydroxy-2,5-dihydro-1,2,4-triazinyl and 5-oxo-6-hydroxy-4,5-dihydro-1,2,4-triazinyl both optionally substituted by a C1-C3 alkyl group; or m)  tetrazolo-pyridazinyl optionally substituted by (a') an optionally salified carboxy group or (b') a group    wherein R' and R" are as defined above; provided that when Y' is a group -S-He-t' wherein Het' is 1,2,3,4-tetrazol-5-yl substituted by C1-C6 alkyl at the 1-position, then R'1 is not .alpha.-hydroxy-i-sopropyl, and the pharmaceutically or veterinarily acceptable salts thereof.