Synthesis of ticagrelor analogues belonging to 1,2,3-triazolo[4,5-d]pyrimidines and study of their antiplatelet and antibacterial activity

The crystal structure of 3,4-dihydroxybenzoic acid – 3-[7-{[2-(3,4-difluorophenyl)cyclopropyl]amino}-5-(propylsulfanyl)-3H-[1,2,3] triazolo[4,5-d]pyrimidin-3-yl]-5-(2-hydroxyethoxy)cyclopentane-1,2-diol – water (1/1/1), C30H36F2N6O9S

C30H36F2N6O9S, orthorhombic, P212121 (no. 19), a = 5.2364(8) Å, b = 10.0250(14) Å, c = 59.689(9) Å, V = 3133.4(8) Å3, Z = 4, Rgt (F) = 0.0384, wRref (F 2) = 0.0969, T = 170 K.

Ultrasensitive and Specific Detection of Anticancer Drug 5-Fluorouracil in Blood Samples by a Surface-Enhanced Raman Scattering (SERS)-Based Lateral Flow Immunochromatographic Assay

5-Fluorouracil (5-FU) is an effective anticancer drug widely used in the world. To improve therapy efficiency and reduce side effects, it is very important to frequently detect the concentration of 5-FU in blood samples of patients. In this work, a new type of lateral flow immunochromatographic assay (LFIA) based on surface-enhanced Raman scattering (SERS) for ultrasensitive and specific detection of 5-FU in blood samples was developed. Au@Ag/Au nanoparticles (NPs) employing Au particles as the core and Ag/Au alloy as the shell were synthesized, characterized and used as the substrate in SERS-LFIA due to their high SERS enhancement and biocompatibility. The immunoprobe was made in the form of AuMBA@Ag/Au-Ab in which mercaptobenzoic acid (MBA, a common Raman active reporter) was embedded in the core-shell layer and the monoclonal antibody (mAb) against 5-FU was immobilized on the surface. The performance of SERS-LFIA was similar to that in colloidal gold based-LFIA, and the entire assay time was within 20 min. According to the color intensity on the testing (T) lines of LFIA strips visualized by eyes, the contents of 5-FU in the samples could be qualitatively or semi-quantitatively identified. Furthermore, by measuring the characteristic Raman intensities of MBA on T lines, quantitative detection of 5-FU in the samples were achieved. The IC50 and limit of detection (LOD) of the LFIA for 5-FU were found to be 20.9 pg mL-1 and 4.4 pg mL-1, respectively. There was no cross-reactivity (CR) of the LFIA with nine relative compounds, and the CR with cytosine, tegafur and carmofur were less than 4.5%. The recoveries of 5-FU from spiked blood samples were in the range of 78.6~86.4% with the relative standard deviation (RSD) of 2.69~4.42%. Five blood samples containing 5-FU collected from the Cancer Hospital were measured by SERS-LFIA, and the results were confirmed by LC-MS/MS. It was proven that the proposed method was able to simply and rapidly detect 5-FU in blood samples with high sensitivity, specificity, accuracy and precision.

Construction of a Pyrimidine Framework through [3 + 2 + 1] Annulation of Amidines, Ketones, and N,N-Dimethylaminoethanol as One Carbon Donor

An efficient, facile, and eco-friendly synthesis of pyrimidine derivatives has been developed. It involves a [3 + 2 + 1] three-component annulation of amidines, ketones, and one carbon source. N,N-Dimethylaminoethanol is oxidized through C(sp³)-H activation to provide the carbon donor. One C-C and two C-N bonds are formed during the oxidative annulation process. The reaction shows good tolerance to many important functional groups in air, making this methodology a highly versatile alternative, and significant improvement to the existing methods for structuring a pyrimidine framework, especially 4-aliphatic pyrimidines.

Benzimidazoazapurines: Design, Synthesis, and Photophysical Study

A highly efficient approach to a new class of polycyclic 8-azapurines, benzo[4,5]imidazo[1,2-a][1,2,3]triazolo[4,5-e]pyrimidines (BITPs), with good photophysical characteristics is proposed. The approach comprises condensation of aminobenzimidazoles with 3-oxo-2-phenylazopropionitrile to form 3-(arylazo)benzo[4,5]imidazo[1,2-a]pyrimidine-4-amines, which undergo oxidative cyclization by the catalytic action of copper(II) acetate, resulting in BITPs with 73-84% yield. Spectral investigations demonstrated the fluorescent properties of BITPs, exhibiting good quantum yields (up to 60%) with maxima absorption at 379-399 and emission at 471-505 nm.