Synthesis and Biological Evaluation of 2,4,6-Functionalized Derivatives of Pyrido[2,3-d]pyrimidines as Cytotoxic Agents and Apoptosis Inducers

Kinase Inhibitors of Novel Pyridopyrimidinone Candidates: Synthesis and In Vitro Anticancer Properties

A new class of pyridopyrimidinone compounds containing different nitrogenous heterocycles were synthesized starting from the key precursor 2-hydrazinyl-5-phenyl-7-(pyridin-3-yl)pyrido[2,3-d]pyrimidin-4(3H)-one via condensation with series of aromatic aldehydes and cyclization using different reagents as ethyl acetoacetate, ethyl cyanoacetate, diethyl malonate, and ammonium isothiocyanate. The bioassay results showed compound 6 to be highly effective towards three human cancer cell lines (HepG2, PC-3, and HCT-116) in vitro with promising activity values (IC50: 0.5 μM) relative to the standard doxorubicin (IC50: 0.6 μM). Kinase inhibitory evaluation of compound 6 displays hopeful inhibitory action against BRAF V600E, EGFR, and PDGFRβ at100 μM. The molecular docking studies supported the initial kinase assay.

Sulfur and selenium derivatives of quinazoline and pyrido[2,3-d]pyrimidine: synthesis and study of their potential cytotoxic activity in vitro

The synthesis, cytotoxic activities and selectivities of 35 derivatives related to quinazoline and pyrido[2,3-d]pyrimidine are described. The synthesized compounds were screened in vitro against four tumoral cell lines - leukemia (CCRF-CEM), colon (HT-29), lung (HTB-54) and breast (MCF-7) - and two cell lines derived from non-malignant cell lines, one mammary (184B5) and one from bronchial epithelium (BEAS-2B). MCF-7 and HTB-54 were the most sensitive cell lines with GI(50) values below 10μM for eleven and ten compounds, respectively. Two compounds (2o and 3a) were identified that evoked a marked cytotoxic effect in all cell lines tested and one compound, 7h, was potent and selective against MCF-7. A preliminary study into the mechanism of the potent derivatives 2o, 3a and 7h indicated that the cytotoxic activities of these compounds might be mediated by inducing cell death without affecting cell cycle phases.

New insights into the structural requirements for pro-apoptotic agents based on 2,4-diaminoquinazoline, 2,4-diaminopyrido[2,3-d]pyrimidine and 2,4-diaminopyrimidine derivatives

As a continuation of our work on new anti-tumoral derivatives with selective pro-apoptotic activity in cancer cells, we describe the synthesis and the preliminary evaluation of the cytotoxic and pro-apoptotic activities of a series of pyrimidin-2,4-diamine derivatives that are structurally related to quinazolin-2,4-diamine and pyrido[2,3-d]pyrimidin-2,4-diamine derivatives. We also describe the structure-activity relationship studies carried out on four series' of quinazolin-2,4-diamine, 2-(alkylsulfanyl)-N-alkyl- and 2-(alkylsulfanyl)-N-alkylarylpyrido[2,3-d]pyrimidine and pyrimidin-2,4-diamine derivatives. The proposed preliminary pharmacophore consists of a flat heterocyclic ring, preferably a pyrido[2,3-d]pyrimidine, with two equivalent alkylarylamine chains, preferably N-benzyl- or N-ethylphenylamine, located in positions 2 and 4 of the ring, and with a preferred ALogP in the range 4.5-5.5. The nitrogen present in the central ring can act as hydrogen bond acceptors (HBA) whereas the amino group in the 4-position can act as a donor (HBD) or an HBA and the amino group in the 2-position can act as an HBD. On the basis of the analyzed structural profiles, different mechanisms of action can be suggested for the quinazolin-2,4-diamine, the 2-(alkylsulfanyl)-N-alkylpyrido[2,3-d]pyrimidin-4-amine and the pyrido[2,3-d]pyrimidin-2,4-diamine derivatives.

Diversity oriented syntheses of fused pyrimidines designed as potential antifolates

Diversity oriented syntheses of some furo[2,3-d]pyrimidines and pyrrolo[2,3-d]pyrimidines related to folate, guanine, and diaminopyrimidine-containing drugs have been developed for the preparation of potential anti-infective and anticancer compounds. Amide couplings and Suzuki couplings on the basic heterocyclic templates were used, in the latter case yields being especially high using aromatic trifluoroborates as the coupling partner. A new ring synthesis of 6-aryl-substituted deazaguanines bearing 2-alkylthio groups has been developed using Michael addition of substituted nitrostyrenes. Diversity at C-2 has been introduced by oxidation and substitution with a range of amino nucleophiles. The chemical reactivity of these pyrrolopyrimidines with respect to both electrophilic substitution in ring synthesis and nucleophilic substitution for diversity is discussed. Several compounds were found to inhibit pteridine reductases from the protozoan parasites Trypanosoma brucei and Leishmania major at the micromolar level and to inhibit the growth of Trypanosma brucei brucei in cell culture at higher concentrations. From these results, significant structural features required for inhibition of this important drug target enzyme have been identified.