Chemical transformations of 2,4-diaryl-2,3-dihydro-1H,1,5-benzodiazepines

Tautomerism of diazepines fused with pyrimidine rings

“…The 1 H nmr spectra of 9a, c, f are listed in Table 2. For 8-(4bromophenyl)-2,3,4,7-tetrahydro-1,3-dimethyl-6-phenyl-1Hpyrimido [4,5-b] [1,4]diazepine-2,4-dione (9c), the following 13 C nmr signals were found in DMSO-d 6 The crystals of 9a (C 21 H 18 N 4 O 2 ) are monoclinic. At 293K was found a = 11.358(2), b = 9.435(2), c = 17.502(4) Å, β = 104.12(3), V = 1818.9(6) Å 3 , space group P2 1 /c, Z = 4, d calc = 1.309 g/cm 3 .…”

“…The precipitate formed was collected by filtration and washed with hot water. Recrystallisation from methanol led to the analytically pure products 7b -d; their 1 H and 13 C nmr spectral data are listed in Tables 2 and 3, respectively. 8-(4-Chlorophenyl)-6-phenyl-9H-pyrimido [4,5-b] [1,4] The general procedures for the preparation of the 6-amino-1,3dimethyl-5-(3-oxo-1,3-diaryl-1-propenylamino)-1,2,3,4-tetrahydropyrimidine-2,4-diones 8a, c, f, the respective 6,8-diaryl-2,3,4,7tetrahydro-1,3-dimethyl-1H-pyrimido [4,5-b] [1,4]diazepine-2,4diones 9a, c, f and their mass spectra are described in the literature [2]. The 1 H nmr spectra of 9a, c, f are listed in Table 2.…”

“…The structural assignment based on nmr measurements is in accordance with ab initio calculations and an X-ray crystal structure analysis. (2) O (1) -C (1) -C (7) 123.9(2) N (1) -C (2) 1.389(3) N (1) -C (1) -C (7) 115.9(2) N (1) -C (8) 1.468(3) O (2) -C (2) -N (2) 122.7(2) N (2) -C (2) 1.373(2) O (2) -C (2) -N (1) 121.2(2) N (2) -C (3) 1.392(2) N (2) -C (2) -N (1) 116.1. (2) N (2) -C (9) 1.471(3) N (3) -C (3) -C (7) 125.7(2) N (3) -C (4) 1.296(2) N (3) -C (3) -N (2) 113.5(2) N (3) -C (3) 1.372(2) C (7) -C (3) -N (2) 120.2(2) N (4) -C (6) 1.290(2) N (3) -C (4) -C (10) 117.2(2) N (4) -C (7) 1.385(2) N (3) -C (4) -C (5) 120.7(2) O (1) -C (1) 1.224(2) C (10) -C (4) -C (5) 121.5(2) O (2) -C (2) 1.218(2) C (4) -C (5) -C (6) 104.2(2) C (1) -C (7) 1.464(3) N (4) -C (6) -C (16) 119.2(2) C (3) -C (7) 1.380(3) N (4) -C (6) -C (5) 119.9(2) C (4) -C (10) 1.478(3) C (16) -C (6) -C (5) 120.9(2) C (4) -C (5) 1.501(3) C (3) -C (7) -N (4) 125.7(2) C (5) -C (6) 1.518(3) C (3) -C (7) -C (1) 119.2(2) C (6) -C (16) 1.479(3) N (4) -C (7) -C (1) 114.6(2) C (15) -C (10) -C (4) 122.2(2) C (1) -N (1) -C (2) 125.2(2) C (11) -C (10) -C (4) 119.8(2) C (1) -N (1) -C (8) 117.6(2) C (21) -C (16) -C (6) 119.4(2) C ...…”

“…The interest in these compounds is based on their biological and pharmacological properties; thus, a series of publications on pyrimido [4,5-b] [1,4]diazepines appeared recently [5][6][7][8][9][10][11][12].…”

“…In continuation of our investigation on nitrogen-containing seven-membered heterocycles [1][2][3][4] we studied the tautomerism of 1,4-diazepines fused with pyrimidine rings. The interest in these compounds is based on their biological and pharmacological properties; thus, a series of publications on pyrimido [4,5-b] [1,4]diazepines appeared recently [5][6][7][8][9][10][11][12].…”