Synthesis, Reactions, and Anti-inflammatory Activity of Heterocyclic Systems Fused to a Thiophene Moiety Using Citrazinic Acid As Synthon

Synthesis and Antitumor Evaluation of Novel Dihydropyrimidine, Thiazolo[3,2-a]Pyrimidine and Pyrano[2,3-d]Pyrimidine Derivatives

“…The structure assigned to the synthesized compounds was 13 C NMR spectrum corresponding to the CH-CN proved the formation of the tautomeric form 2e'.…”

“…Meanwhile, 1 H NMR spectrum showed a singlet at δ 6.09 ppm for CH of the thiazole ring with the disappearance of signals corresponding to SH and pyrimidine H-5. At the same time 13 The reaction of the arylaldehydes 1a-e, ethyl acetoacetate and thiourea in 1,4 dioxane using triethylamine as the catalyst afforded 1,4-dihydromercaptopyrimidines 7a-d and chromeno [4,3-d]pyrimidine 7e (Scheme 3). The 1 H NMR spectrum of 7a showed beside the expected signals the presence of singlets at δ 5.17, 9.6 and 10.29 ppm corresponding to the presence of CH pyrimidine, NH and SH, respectively.…”

“…11,20 Thiazolo[3,2-a]pyrimidine 3b and pyrano [2,3-d]pyrimidines 32 4b, 5b (Scheme 2) were obtained from the reaction of 4,5-dihydropyrimidine derivative 2b with ω-bromo-4-chloroacetophenone, hydrazine hydrate and phenyl hydrazine, respectively. The structure of these compounds was elucidated by IR, 1 H and 13 C NMR spectra beside their analytical and mass spectral data. Thus, the IR spectrum of 3b showed the absence of any CN signal beside the expected signals.…”

“…4 Among the wide range of compounds tested as potential anticancer agents, pyrimidine and fused pyrimidine derivatives comprise an important class of therapeutic agents. They were reported as antitumor, [5][6][7][8][9][10] antimicrobial, 11,12 antiinflammatory, 13 anti HIV, 14 antinociceptive, 15,16 and antioxidant agents. 17,18 Various drugs containing pyrimidine nucleus were synthesized and used as anticancer agents like 5-fluorouracil (5-FU), tegafur and thioguanine ( Figure 1).…”

Synthesis and in-vitro studies of some new quinoline 1,3,4-thiadiazolo pyrimidin derivatives

“…It is known that many 1,3,4-thiadiazoles have biological activities like antibacterial [9], antimycobacterial [10], antimycotic [11], antifungal [12], antidepression [13], analgesic [14] and anti-inflammatory [15]. Nitrogen containing heterocyclic ring such as pyrimidine and its derivatives have been reported as anti-microbial [16], analgesic, anti-viral, anti-inflammatory [17], anti-HIV [18], anti-tubercular [19], anti-tumour [20], anti-neoplastic [21], anti-malarial [22], diuretic [23], cardiovascular [24] agents. Here in, we report a series of eight new quinoline associated 1,3,4-thiadiazolo pyrimidin derivatives.…”