Interestingly, in some examples of bioactive heterocycles, a more pronounced effect is observed when two or more different heterocyclic moieties are incorporated within a single molecule.[1] In this context, recent attention is focused on construction of structures with multiple heterocycles, as well as on the creation of heterocyclic diversity from common precursors. 5-(2,4-Dioxo-7-{2-methyl-phenyldiazo}-2,3,4,5-tetrahydro-1H-chromeno[2,3-d]pyrimidin-5-yl)pyr... mp 275-277 SP 0 sp C; IR (ATR): 3430, 3198, 3062, 3024, 2851, 2803, 1716, 1691, 1624, 1528, 1484, 1421, 1364, 1298, 1238 cm SP -1 sp ; SP 1 sp H NMR (300 MHz, DMSO-d SB 6 sb ): 2.66 (s, 3H), 4.01 (d, 1H, I J= i 2.1Hz), 4.84-4.85 (d, 1H, I J= i 1.8Hz), 7.30-7.33 (d, 2H, Ar-H, I J= i 8.7Hz), 7.44 (s, 2H, Ar-H), 7.53-7.56 (d, 1H, Ar-H, I J= i 7.8Hz), 7.7 (s, 1H, Ar-H), 7.85-7.88 (d, 1H, Ar-H, I J= i 8.7Hz), 11.08 (s, 1H, -NH), 11.19 (s, 1H, -NH), 11.25 (s, 1H, -NH), 11.37 (s, 1H, -NH). 2-{5-[(E)-(4-Chlorophenyl)diazenyl]-2-hydroxyphenyl}-2,3-dihydroquinazolin-4(1H)-one (5d) mp 330 SP 0 sp C; IR (ATR): 3300, 3175, 3058, 2878, 1678, 1608, 1482, 1375, 1257 cm SP -1 sp ; SP 1 sp H NMR (400 MHz, DMSO-d SB 6 sb ): 6.09 (s, 1H), 6.43 (s, 1H), 6.62- 6.67 (t, 1H, I J= i 3.2Hz), 6.74-6.76 (d, 1H, Ar-H, I J= 8 i Hz), 6.96-7.00 (t, 1H, Ar-H, I J= i 8Hz), 7.15-7.19 (t, 1H, Ar-H, I J= i 8Hz), 7.41-7.43 (t, 2H, Ar-H, I J= 8 i Hz), 7.66-7.75 (m, 4H, Ar-H), 7.84 (s, 1H), 8.00 (s, 1H), 10.51 (s, 1H, -OH). 5-{2-Hydroxy-5-[(E)-2-chlorophenyldiazenyl]phenyl}-1,2,4-triazolidine-3-thione (6c) mp 273-275 SP 0 sp C; IR (ATR): 3428, 3246, 3151, 2875, 1604, 1511, 1356, 1269, 1105 cm SP -1 sp ; SP 1 sp H NMR (400 MHz, DMSO-d SB 6 sb ): 7.00-7.03 (q, 1H, Ar-H, I J= i 8.8Hz), 7.34-7.42 (m, 2H), 7.53-7.63 (m, 2H, Ar-H), 7.76-7.78 (d, 2H, Ar-H, I J= i 8.8Hz), 8.00-8.03 (d, 1H, Ar-H I J= i 10Hz), 8.41 (s, 1H), 8.42 (s, 1H), 10.56 (s, 1H, -NH), 11.46 (s, 1H, -NH). [Extracted from the article]