Discovery of pyrazolo[3,4-b]pyridine derivatives as novel and potent Mps1 inhibitors for the treatment of cancer

Monopolar spindle kinase 1 (Mps1) is a key element of the mitotic checkpoint and clinically evaluated as a target in the treatment of aggressive tumors. With this aim, a set of pyrazolo[3,4-b]pyridine-based compounds as new Mps1 inhibitors was investigated through a multidisciplinary approach, based on virtual screening, chemical synthesis and biological evaluation. One of the representative compounds, 31, exhibited strong kinase inhibitory potency against Mps1 with an IC₅₀ value of 2.596 nM and significantly inhibited proliferation of cancer cells, especially MDA-MB-468 and MV4-11 cells. Compound 31 also displayed reasonable kinome selectivity against a panel of 606 wild-type kinases at 1 μM. Moreover, compound 31 exhibited suitable preclinical pharmacokinetic parameters and a promising pharmacodynamic profile. Further, compound 31 showed good antitumor efficacy in MDA-MB-468 xenograft model with no obvious toxicity. Overall, compound 31 was identified as a potential Mps1 inhibitor for cancer therapy and deserve further research.

Molecular Hybrids of Pyazolo[3,4-b]pyridine and Triazole: Design, Synthesis and In Vitro Antibacterial Studies

Antimicrobial resistance is on the rise, and there aren't enough new treatments to combat it. This might send the modern world back to the pre-antibiotic age. The molecular hybrids of pyrazolo[3,4-b]pyridine and triazole have been designed, synthesized, and analyzed for their drug-like molecule nature and in vitro analyses for their inhibition potentials against S. aureus and K. pneumoniae. The compounds 24 and 27 have been identified as the high potential molecules in this series based on in vitro experiments. Compound 24 has zone of inhibition values of 15 ± 0.82 mm and 14 ± 0.7 mm, whilst compound 27 has zone of inhibition values of 18 ± 0.95 mm and 16 ± 0.82 mm against S. aureus and K. pneumoniae, respectively. MIC and MIB values for compounds 24 and 27 against S. aureus and K. pneumoniae are 0.25 and 0.5, respectively.

Synthesis and biological evaluation of novel pyrazolo[3,4-b]pyridines as cis-restricted combretastatin A-4 analogues

Twenty-six novel pyrazolo[3,4-b]pyridine-bridged analogues of combretastatin A-4 possessing 3,4,5-trimethoxylphenyl groups, were synthesized and evaluated for their antiproliferative and tubulin polymerization inhibitory activities. Preliminary biological evaluation demonstrated that some of the target compounds displayed significant antiproliferative effectagainst four different cell lines including MCF-7, MDA-MB-231, HeLa and Kyse150. The most active analogue 6n was found to induce HeLa cells arrest in the G2/M phase in a dose-dependent manner. Molecular modeling studies indicated that derivative 6n most likely occupies the colchicine site of tubulin. The initial results suggest that the 3,4,5-trimethoxyphenyl substituted pyrazolo[3,4-b]pyridine could serve as a promising scaffold for development of potent tubulin inhibitors as anticancer agents.

Synthesis of novel ethyl 2,4-disubstituted 8-(trifluoromethyl)pyrido[2',3':3,4]pyrazolo[1,5-a]pyrimidine-9-carboxylate derivatives as promising anticancer agents

A series of novel pyrido[2',3':3,4] pyrazolo[1,5-a]pyrimidine derivatives 6-9 were prepared in single step starting from 3-amino-6-(trifluoromethyl)-1H-pyrazolo[3,4-b]pyridine-5-carboxylate 5 on reaction with symmetrical and unsymmetrical aliphatic and aromatic 1,3-diketones/α,β unsaturated ketones/α,β unsaturated keto ethers under conventional method. All the final compounds 6a-c, 8a-b and 9a-l were screened for anticancer activity against five human cancer cell lines such as PC-3 (CRL-1435), MDA-MB-231 (HTB-26), Hep G2 (HB-8065), HeLa (CCL-2) and normal HUVEC (CRL-1730). Compounds 8a, 9f and 9k which showed promising anticancer activity have been identified. Further, the promising compounds (8a and 9f) were able to inhibit the human topoisomerase I (TopI) activity similar to that of camptothecin.

Synthesis of novel hydrazone and azole functionalized pyrazolo[3,4-b]pyridine derivatives as promising anticancer agents

A series of novel pyrazolo[3,4-b]pyridine based target compounds were synthesized starting from the key intermediate ethyl 2-(3-amino-6-(trifluoromethyl)-1H-pyrazolo[3,4-b]pyridin-1-yl)acetate 5 on reaction with hydrazine hydrate followed by reaction with different aldehydes, acid chlorides and isothiocyanates to form hydrazones 7, oxadiazoles 8, 1,2,4 triazoles 10 and thiadiazoles 11 respectively in high yield. All the final compounds were screened for anticancer activity against four human cancer cell lines. Among them, 1,2,4 triazole derivatives showed promising activity and compound 10d is identified as a lead molecule.

Synthesis and antimicrobial activity of some new heterocycles incorporating the pyrazolopyridine moiety

2-Cyano-N-(4,6-dimethyl-1H-pyrazolo[3,4-b]pyridin-3-yl)acetamide (2) was utilized as key intermediate for the synthesis of some new coumarin 3, pyridine 4, pyrrole 5, thiazole 8, pyrido[2',3':3,4]-pyrazolo-[5,1-c]triazine 7, and aminopyrazolo 10 compounds. 2-Cyano-N-(4,6-dimethyl-1H-pyrazolo[3,4-b]pyridin-3-yl)-3-(dimethylamino)acrylamide (11) was synthesized and allowed to react with hydroxylamine, hydrazine, and guanidine to afford regioselectively the isoxazole 13, pyrazole 15, and pyrimidine 17 derivatives, respectively. The reaction of 11 with thiourea and/or with ethyl glycinate in basic medium afforded the regioisomeric pyrimidinethione 18 and 3,5-dioxo-1,4-diazepine-6-carbonitrile 23. All the synthesized products were tested and evaluated as antimicrobial agents.

Synthesis and biological evaluation of novel alkyl amide functionalized trifluoromethyl substituted pyrazolo[3,4-b]pyridine derivatives as potential anticancer agents

A series of novel alkyl amide functionalized trifluoromethyl substituted pyrazolo[3,4-b]pyridine derivatives 5, 6 and 7 were prepared starting from 6-phenyl-4-(trifluoromethyl)-1H-pyrazolo[3,4-b]pyridin-3-amine 3 via selective N-alkylation, followed by reaction with different primary aliphatic amines, cyclic secondary amines or l-amino acids under different set of conditions. All the synthesized compounds 5, 6 and 7 were screened for anticancer activity against four cancer cell lines such as A549-Lung cancer (CCL-185), MCF7-Breast cancer (HTB-22), DU145-Prostate cancer (HTB-81) and HeLa-Cervical cancer (CCL-2). The compounds 5i and 6e are found to have promising bioactivity at micro molar concentration.