5+1-Heterocyclization as preparative approach for carboxy-containing triazolo[1,5-c]quinazolines with anti-inflammatory activity.

Present article is devoted to the purposeful search of novel anti-inflammatory agents among carboxyl-containing partially hydrogenated [1,2,4]triazolo[1,5-с]quinazolines and products of their tandem cyclization. It has been shown that target compound's could be obtained via interaction between [2-(3-R-1H-1,2,4-triazol-5-yl)phenyl]amines and oxo-containing carboxylic acids and their esters of various structure. The structures of synthesized compounds were verified by appropriate methods, the features of NMR-spectra patterns were discussed as well. The low predicted toxicity of obtained compounds has been estimated using in silico methods. In vivo study on the model of acute aseptic inflammation (carrageenan test) have been revealed that synthesized compounds expose anti-inflammatory activity in the range of 0.94-52.66%. 4-(2-(Ethoxycarbonyl)-5,6-dihydro-[1,2,4]triazolo[1,5-c]quinazolin-5-yl)benzoic acid has been identified as most active compound. Additionally, the effects of some (2-R-5,6-dihydro[1,2,4]triazolo[1,5-c]quinazolin-5-yl)benzoic acids (compounds 3) on the levels of key inflammatory markers have been estimated. It has been shown that studied compounds decrease the level of neutrophils, COX-2, nitrotyrosine, IL-1b, C-reactive protein and increase level of eNOS. 4-(2-(Ethoxycarbonyl)-5,6-dihydro-[1,2,4]triazolo[1,5-c]quinazolin-5-yl)benzoic acid (3.2) has been identified as compound with most expressed anti-inflammatory activity and significant effect on the levels of marker of inflammatory processes. Molecular docking study towards СОХ-1 and СОХ-2 has been conducted to substantiate possible mechanism of obtained compounds anti-inflammatory activity. It has been found that fixation of 4-(2-(ethoxycarbonyl)-5,6-dihydro-[1,2,4]triazolo[1,5-c]quinazolin-5-yl)benzoic acid (3.2) molecule in active site of enzyme is outstandingly similar to the reference ligands. The essential value of carboxylic group for presence of anti-inflammatory activity has been estimated as result of SAR-analysis. It has been found that studied class of compounds is perspective for further structural modification aimed to the creation of novel anti-inflammatory agents.

2-[(3-Aminoalkyl-(alkaryl-,aryl-))-1H-1,2,4-triazol-5-yl]anilines: synthesis and anticonvulsant activity.

The presented work is devoted to the development of synthesis methods for novel 2-[(3-aminoalkyl-(alkaryl-, aryl-))-1H-1,2,4-triazolo]anilines. Abovementioned compounds were obtained via hydrazinolysis (Ing-Manske procedure) and acid hydrolysis of corresponding N -acylated{([1,2,4]triazolo[1,5-c]quinazolin-2-yl)alkyl-(alkaryl-, aryl-)}amines. The regioselectivity of hydrazinolysis and hydrolysis were established. The features of spectral characteristics werestudied and discussed. Characteristic patterns of protons signals splitting in 1H NMR of the synthesized compounds were established. The effect of the synthesized compounds on the pentylenetetrazol seizures was studied. It was found that according to some indicators, anticonvulsant activity of 2-[(3-aminoalkyl-(alkaryl-, aryl-))-1H-1,2,4-triazolo]anilines superior or comparable with effect of the reference drug "Lamotrigine". It is a valid argument for their further structural modification, in-depth study of activity mechanisms and further study of anticonvulsant activity on other experimental seizures models.

Directed Search of Anti-inflammatory Agents Among (3HQuinazoline- 4-ylidene)hydrazides of N-protected Amino acids and their Heterocyclization Products.

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.

Synthesis and Antimicrobial Activity of 6-Thioxo-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]-quinazolin-2-one Derivatives.

Potassium 8-R(1)-9-R(2)-10-R(3)-3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazoline-6-thiolates 2.1-2.26 were synthesized via cyclocondensation of 6-R-3-(3-R(1)-4-R(2)-5-R(3)-aminophenyl)-1,2,4-triazin-5-ones 1.1-1.26 with carbon disulfide, potassium hydroxide, and ethanol or with potassium O-ethyl dithiocarbonate in 2-propanol. The corresponding thiones 3.1-3.26 were obtained by treatment of 2.1-2.26 with hydrochloric acid. It was found that the nature of the substituents in positions 3, 4, and 5 of the corresponding 6-R-3-(3-R(1)-4-R(2)-5-R(3)-aminophenyl)-1,2,4-triazin-5-ones were affected on the terms of the reaction. The structures of compounds were proven by a complex of physicochemical methods ((1)H, (13)C NMR, LC-MS, and EI-MS). The results of the antibacterial and antifungal activity assay allowed the determination of the high sensitivity of Staphylococcus aureus ATCC 25923 (MIC 6.25-100 µg/mL, MBC 12.5-200 µg/mL) to the synthesized compounds.

Substituted 2-[(2-Oxo-2H-[1,2,4]triazino [2,3-c]quinazolin-6-yl)thio]acetamides with Thiazole and Thiadiazole Fragments: Synthesis, Physicochemical Properties, Cytotoxicity, and Anticancer Activity.

The series of novel N-R-2-[(3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazolin-6-yl)thio]acetamides with thiazole and thiadiazole fragments in a molecule were obtained by alkylation of potassium salts 1.1-1.4 by N-hetaryl-2-chloroacetamides and by aminolysis of activated acids 2.1-2.4 with N,N'-carbonyldiimidazole (CDI). The structures of compounds were determined by IR, (1)H NMR, MS, and EI-MS analysis. The results of cytotoxicity evaluated by the bioluminescence inhibition of bacterium Photobacterium leiognathi, Sh1 showed that the compounds have considerable cytotoxicity. The synthesized compounds were tested for anticancer activity in NCI against 60 cell lines. Among the highly active compounds 3.1, 3.2, and 6.5, 2-[(3-methyl-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazolin-6-yl)thio]-N-(1,3-thiazol-2-yl)acetamide (3.1) was found to be the most active anticancer agent against the cell lines of colon cancer (GI(50) at 0.41-0.69 µM), melanoma (GI(50) 0.48-13.50 µM), and ovarian cancer (GI(50) 0.25-5.01 µM). The structure-activity relationship (SAR-analysis) was discussed.

Synthesis of New 6-{[ω-(Dialkylamino(heterocyclyl)alkyl]thio}-3-R-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones and Evaluation of their Anticancer and Antimicrobial Activities.

Several novel 6-thio-3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazoline-based compounds containing an ω-(dialkylamino(heterocyclyl)]alkyl fragment were synthesized 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. Alternatively, compounds 3.1-3.22 were synthesized by alkylation of 3-R-6-thio-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones potassium salts (1.1-1.4) with (2-chloroethyl)-N,N-dialkylamine hydrochlorides or 1-(2-chloroethyl)heterocycle hydrochlorides. The structures of compounds were elucidated by (1)H, (13)C NMR, LC-MS and EI-MS analysis. Then anticancer and antibacterial, bioluminescence inhibition of Photobacterium leiognathi Sh1 activities of the substances 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, colon, CNS, ovarian, renal, prostate, breast, melanoma and leukemia (log GI(50) < -5.65). The "structure-activity" relationship was discussed. COMPARE analysis for synthesized anticancer active compounds was performed.