Disclosed are benzoxazines and benzothiazines of formula (I) EMBED ISISServer , (I) wherein Q is O-(CHR6)l-3 or S-(CHR6)1-3 R1 and each R6 is H, optionally substituted [C1-6 alkyl, C1-4alkaryl, C1-4 alkheterocyclyl, C2-9 heterocyclyl, C3-8 cycloalkyl, C1-4 alkcycloalkyl] or - (CR1AR1B)nNR1cRlD wherein R1A, R1B, R1C, R1D are independently hydrogen, optionally substituted [C1-6 alkyl, C1-4alkaryl, C1-4 alkheterocyclyl, C2-9 heterocyclyl, C3-8 cycloalkyl, etc.] or wherein R1A and R1B combine to form=O, or wherein R1C and R1D combine to form an optionally substituted C2-9 heterocyclyl, and n is an integer between 1-6 each of R2 and R3 is H, hal, optionally substituted [C1-6 alkyl, C6-10aryl, C1-6alkaryl, C2-9 heterocyclyl, C1-6 alkoxy, C1-6 thioalkoxy, (CH2)r2NHC(NH)R2A, CH2)r2NHC(S)NHR2A, C1-4 alkheterocyclyl] or hydroxyl, wherein r2 is an integer from 0 to 2, R2A is optionally substituted [C1-6 alkyl, C6-10aryl, C1-4 alkaryl, C2-9 heterocyclyl, C1-4 alkheterocyclyl, C1-6 thioalkoxy, C1-4 thioalkaryl, aryloyl, C1-4thioalkheterocylyl, or amino] each R4 and R5 is H, hal, (CH2)r2NHC(NH)R2A or CH2)r2NHC(S)NH R2A Y1 and Y2 are together=O or Y1 and Y2 are independently H, optionally substituted [C1-6 alkyl, C6-10aryl, C1-6alkaryl, C2-9 heterocyclyl, C1-6 alkoxy, C1-6 thioalkoxy, C1-4alkheterocyclyl] or hydroxy wherein only one of R2, R3, R4 and R5 is (CH2)r2NHC(NH)R2A or CH2)r2NHC(S)NH R2A or a pharmaceutically acceptable salt or prodrug thereof. Said benzoxazines and benzothiazines of formula (I) inhibit nitric oxide synthase (NOS), particularly selectively inhibit neuronal nitric oxide synthase (nNOS) in preference to other NOS isoforms. The NOS inhibitors of formula (I), alone or in combination with other pharmaceutically active agents, can be used for treating or preventing various medical conditions.(I)Описані бензоксазини і бензотіазини формули (І), в якій Q являє собою О-(CHR)або S-(CHR)Rі кожен Rявляють собою Н, необовязково заміщений [Салкіл, Салкарил, Салкгетероцик
