FIELD: organic chemistry. SUBSTANCE: product: derivative of 1,4-benzothazepine of the formula (I) 
where: R means H or lower C1-C3-alkoxy-group; X means O or H2; n = 1 or 2; R1 means H, phenyl group substituted with OH or lower C1-C3-alkoxy-group, group of the formula 
, lower C1-C3-alkoxy-group or group of the formula: 
where: R2 means C1-C3-acyl-group and NH means phenyl group, or their pharmaceutically acceptable salts. Synthesized compounds shows inhibiting effect of myocardium without by-side cardiodepressing effect. EFFECT: improved method of chemistry, enhanced effectiveness. 1 tbl
