A facile method for preparation and evaluation of the antimicrobial efficiency of various heterocycles containing thieno[2,3-d]pyrimidine

Solid-State Luminescent Materials Containing Both Indole and Pyrimidine Moieties: Design, Synthesis, and Density Functional Theory Calculations

Heterocyclic compounds with effective solid-state luminescence offer a wide range of uses. It has been observed that combining pyrimidine and indole moieties in a single molecule can enhance material behavior dramatically. Here, different heterocyclic compounds with indole and pyrimidine moieties have been synthesized effectively, and their structures have been validated using NMR, IR, and mass spectroscopy. The photoluminescence behavior of two substances was investigated in powder form and solutions of varying concentrations. After aggregation, one molecule displayed a redshifted luminescence spectrum, whereas another homolog showed a blueshift. Thus, density functional theory calculations were carried out to establish that introducing a terminal group allows modifying of the luminescence behavior by altering the molecular packing. Because of the non-planarity, intermolecular interactions, and tiny intermolecular distances within the dimers, the materials demonstrated a good emission quantum yield (Φ_em) in the solid state (ex. 25.6%). At high temperatures, the compounds also demonstrated a stable emission characteristic.

An efficient protocol for the synthesis of new camphor pyrimidine and camphor thiazole derivatives using conventional and microwave irradiation techniques and in vitro evaluation as potential antimicrobial agents

BACKGROUND

A series of new pyrimidines and thiazoles containing camphor moiety were synthesized under both conventional and microwave irradiation techniques.

METHODS

The condensation of camphor either with aminoguanidine or thiosemicarbazide gives the camphor hydrazine carboximidiamide 2 and the camphor thiosemicarbazone 3, respectively. Refluxing of 3 with chloroacetonitrile afforded the camphor thiazol-4-imine 4. Compounds 2 and 4 were used as precursors for the synthesis of target products.

RESULTS

The reaction of 2 with different species such as arylidene malononitrile, acetylacetone, and ethyl acetoacetate gave the corresponding camphor pyrimidine derivatives 5a,b-7 while refluxing of compound 4 with different reagents e.g. aldehydes, isatin, ninhydrin, acetic anhydride, benzene sulphonyl chloride, and p-nitro-benzoyl chloride afforded the camphor thiazole derivatives 8a-d-13, respectively.

CONCLUSION

A comparison between the conventional way and the eco-friendly microwave irradiation method occurred in the synthesis of the same compounds, which the latter was more efficient. The elemental analysis, FT-IR, 1H NMR, 13C NMR, and Mass spectra confirm the structures of the obtained new compounds. The potential use of some selected derivatives as antimicrobial agents was investigated and gave promising results.

Novel thienopyrimidine-aminothiazole hybrids: Design, synthesis, antimicrobial screening, anticancer activity, effects on cell cycle profile, caspase-3 mediated apoptosis and VEGFR-2 inhibition

A series of novel hybrid compounds of hexahydrobenzo[4,5]thieno[2,3-d]pyrimidine with aminothiazole scaffolds were synthesized. The synthesized compounds were evaluated for their cytotoxic activity against the NCI-60 human tumor cell line panel. Compounds 7c, 7d and 7e exhibited significant antiproliferative activities at 10^-5 M dose. Compound 7c exhibited excellent cytotoxic activity against CNS cancer cell lines including SNB-75 and SF-295 as well as renal cancer cell line CAKI-1 when compared with sorafenib as standard anticancer drug. In addition, compound 7d showed almost comparable anticancer activity to sorafenib against SNB-75 cell line and displayed moderate activity against SF-295 and CAKI-1 cell lines in comparison to sorafenib. Compound 7c inhibited the vascular endothelial growth factor receptor 2 (VEGFR-2) with IC₅₀ of 62.48 ± 3.7 nM and decreased both total VEGFR-2 and phosphorylated VEGFR-2 in treated SNB-75 cells suggesting its ability to down regulate cell proliferation, growth, and survival.. The flow cytometric analysis showed that 7c displayed its cytotoxic activity through the reduction of the cellular proliferation and induction of cell cycle arrest at the G2/M phase. Compound 7c clearly boosted the level of the apoptotic caspase-3. All the synthesized compounds were also screened for their antibacterial and antifungal activity against four pathogenic strains of both Gram-positive and Gram-negative as well as Candida albicans. Only compound 7d exhibited antifungal activity against Candida albicans compared to nystatin as the standard antifungal compound.