Lactam derivatives as antagonists for human 11cby receptors

A compound of formula (I) comprising:

• or a salt thereof, wherein
• M is a group selected from the group consisting of O, S, C═O, NH and CH2;
• L is a 2- or 3-membered alkylene chain;
• wherein together M-L may be optionally substituted by at least one moiety selected from the group consisting of methyl, ethyl, hydroxy and C1-3 alkoxy;
• R1 and R2 together with the nitrogen atom to which they are bonded form a pyrrolidinyl;
• each R6 is the same or different and is independently selected from the group consisting of hydroxy, C1-2alkyl, C1-3alkoxy, halo, C2-3alkenyl, benzyl, and —C(Ra)NORb, wherein Ra and Rb are each independently selected from the group consisting of hydrogen, methyl, methoxymethyl, methoxymethoxy, and methoxyethoxy and n is 1, 2, 3, or 4;
• QY is isoindole-1,3-dione;
• shown below as
• Z is bound to the Q ring and is selected from the group consisting of a direct bond, NH, NCH3, O, S, and CH2;
• and
• R3 is a group selected from the group consisting of aryl, alk-2-en-1-yl, cycloalkyl and cycloalk-2-en-1-yl and wherein said aryl, alk-2-en-1-yl, cycloalkyl, and cycloalk-2-en-1-yl are optionally substituted from 1 to 3 times with a substituent selected from the group consisting of C1-3 alkyl, halo, amino, alkylamino, dialkylamino, hydroxy, C1-3alkoxy, cyano, trifluoromethyl, and methylthio groups.