Palladium-catalyzed buchwald- hartwig cross-coupling for 8-chloro-2 metil-benzo[4,5] tiazolo[3,2-a] pyrimidin 4- one

Purprose of the study. Identification of the pharmacological activity and catalytic ability of 8-choloro2-methyl-benzol [4,5] thiazolo[3,2-a] pyrimidin -4 Ona

Materials and research methods. The Buch is the formation of C-N bonds via a palladium cross-coupling reaction between amines and aryl-substituted holides, has also worked wel with various amines and aryl- substituted holides, i.e.8-chloro-2-methylbenzo[4,5] thiazolo [3,2-a] pyrimidin-4 ona with morpholine as a catalyst Pd (dba) CHCL₃ (4, mol%), XPhos ligand (8, mol%) base Na ot Bu, (1,4, equiv) and refluxing in toluene (2 ml) for 16 hours gave 8- morpholino -2- methylbenzo [4,5] thiazolo [3,2-a] 4-ona amounted to 85% and for other amines of the cross- coupling products it was as a percentage: 52 (8 phenylmenthylamino), 72 (8-fluovopheylamino) 56 (8-(3,5- thymenthoxyphenylamino)-2 methylbenzo [4,5] thiazolo [3,2] pyrimidin-4 ona

Results and its discussion. Benzothiazolo [3,2-a] pyrimidin has a wide vange of pharmacological activites, such as: antileishmanial, sedative and antifungal. The Buchwoid – Hartwing cross –coupling reaction between amines and aryl-substitutcal halides, also worked weii with varios amines and heteryl halides, i.e. 8-chloro-2-methylbenzo[4,5]thiazolo[3,2-a] pyridin -4 ona was 85% and for other amines of cross-coupling products was%: 52 (8-phenylmethylamino) 72 (8-fluorophenylamino), 56 (8-(3-trifluoromethylphenylamino) and 63 (8-(3,5- thymethoxyphenylamino)-2-methylbenzo[4,5]thiazolo [3,2-a] pyrimidine -4 ona

Conclussion. 1) Benzothiazolo [3,2-a] pyridine has broad pharmacological activities (antibacterial, antitumor, fungicial, antileishmanial, sedative and antifungal). 2) The Buchnald-Hartwig cross-coupling reaction, which worked well with various amines and halides, i.e. 8-chloro 2- methylbenzo [4,5] gnatolo [3,2-a] pyrimidin – 4 ona. 3) The best results were obtained using Pol (dba) – X CHCl as a catalyst. X Phos as ligand and NaOrBu as base in toluene. The reaction with morpholine gave the product 2 a in 85% yield.

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