Desing, synthesis and anti-inflammatory activity of dirivatives 10-R-3-aryl-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]quinazolin-2-ones of spiro-fused cyclic frameworks

Background: (Quinazoline-4-ylidene)hydrazides are valued intermediates in modern organic chemistry, as they are commonly used for the synthesis of substituted [1,2,4]triazolo[1,5-c]quinazolines.Objective: Unknown N-acyl-2-([1,2,4]triazolo[1,5-c]quinazoline-2-yl)-alkyl-(alkaryl-, aryl-) amines were synthesized and evaluated for anti-inflammatory potential.Methods: The peculiarities of the synthesized compounds structures were studied by IR-, NMR spectroscopy and chromatography-mass spectrometry and were discussed in detail. Probable molecular mechanisms of activity (inhibition of COX-1 and COX-2) were predicted due to molecular docking. Anti-inflammatory activity of synthesized compounds was determined by their ability to reduce the formalin-induced paw edema in rats. Diclofenac sodium was used as reference drug.Results: In this study, the synthesis of N-acetyl-(benzoyl)-2-([1,2,4]triazolo[1,5-c]quinazolinе- 2-yl)alkyl-(aralkyl-, aryl-)amines, using (3H-quinazoline-4-ylidene)hydrazides of Nprotected amino acids or 4-hydrazinoquinazoline and N-prorotected amino acids as starting compounds was developed. It was established that the reaction of (3H-quinazoline-4- ylidene)hydrazides of Boc-amino acids occurred with the formation of N-acetyl-substituted triazoloquinazolines. High anti-inflammatory activity was detected for unknown (3Hquinazoline- 4-ylidene)hydrazides Boc-amino acids (1.13-1.15) and N-acetyl-(benzoyl)-2- ([1,2,4]triazolo[1,5-c]quinazoline-2-yl-)aralkyl-(aryl-)amines (3.2, 3.3, 3.11, 3.12), using the experimental formalin test.Conclusion: The conducted SAR-analysis allowed to detect critical fragments. Namely, the Boc-aminoaralkyl-(aryl-)acid residue in (3H-quinazoline-4-ylidene)hydrazides (1.13- 1.15), benzyl and phenyl linker groups in N-acetyl-(benzoyl)-2-([1,2,4]triazolo[1,5- c]quinazoline-2-yl-)aralkyl-(aryl-) amines (3.2, 3.3, 3.11, 3.12) are believed to be substantial for anti-inflammatory activity.

The death rate from cancer and infectious diseases is still very high, therefore research in this area is extremely important and promising as in medical, so in economic point of view. Thus, potassium salt of tetrazolo[1,5-c]quinazolin-5-thion was modified per alkylation by N-aryl(benzyl,heteryl)acetamides with proper confirmation of newly synthesized compounds’ structures by FT-IR, LC–MS, 1H NMR and elemental analysis data. The substances were tested for bioluminescence inhibition against Photobacterium leiognathi Sh1 (5–50μg/mL) to check their cytotoxicity. Then they were screened for antibacterial and antifungal activities (100μg) against Escherichia coli, Staphylococcus aureus, Enterobacter aerogenes and Enterococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans. It was found that compounds 1.1, 1.5, 1.10, 1.31, 1.33 possessed light activity against K. pneumonia. The US National Cancer Institute (NCI) has chosen 19 compounds and screened them for ability to inhibit in 10μM concentration 60 different human tumor cell lines. The LOX IMVI cell line of melanoma appeared to be the most sensitive one, and N-(6-methylbenzo[d]thiazol-2-yl)-2-(tetrazolo[1,5-c]quinazolin-5-ylthio)acetamide (1.31) and N-(3-fluorobenzyl)-2-(tetrazolo[1,5-c]quinazolin-5-ylthio)acetamide (1.19) exhibited high growth inhibition rate, and N-(6-methoxybenzo[d]thiazol-2-yl)-2-(tetrazolo[1,5-c]quinazolin-5-ylthio)acetamide (1.32) showed lethal antitumor activity against it. The latter compound 1.32 showed the best anticancer results, also inhibiting growth of leukemia SR cell line, NCI-H460 of non-small cell lung cancer, KM12 of colon cancer and SF-295 of CNS cancer. The in silico molecular docking studies have predicted the affinity of the synthesized substances to the epidermal growth factor receptor (EGFR)

Several novel 6-thio-3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazoline-based com-pounds containing an ω-(dialkylamino(heterocyclyl)]alkyl fragment were synthe-sized to examine their anticancer activity. Some of the 6-{[ω-(hetero-cyclyl)alkyl]thio}-3-R-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones (3.1–3.10) were obtained by the nucleophilic substitution of 6-[ω-halogenalkyl]thio-3-R-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones (2.1–2.8) with azaheterocycles. Alter-natively, compounds 3.1–3.22 were synthesized by alkylation of 3-R-6-thio-2Н-[1,2,4]triazino[2,3-c]quinazoline-2-ones potassium salts (1.1–1.4) with (2-chloro-ethyl)-N,N-dialkylamine hydrochlorides or 1-(2-chloroethyl)heterocycle hydro-chlorides. The structures of compounds were elucidated by 1H, 13C NMR, LC–MS and EI-MS analysis. Then anticancer and antibacterial, biolumi-nescence inhibition of Photobacterium leiognathi Sh1 activities of the sub-stances were tested in vitro. It was found that compound 3.18 possessed a wide range of anticancer activity against 27 cell lines of cancer: non-small cell lung, сolon, CNS, ovarian, renal, prostate, breast, melanoma and leukemia (log GI50 < −5.65). The “structure-activity” relationship was discussed. COMPARE analysis for synthesized anticancer active compounds was performed.