In an effort to improve and achieve biologically active anticancer agents, a novel series of 1,2,3-triazole-containing hybrids were designed and efficiently synthesized via the Cu-catalyzed azide-alkyne cycloaddition (CuAAC) reaction of substituted-arylazides with alkyne-functionalized pyrazole-[1,2,4]-triazole hybrids. The structure geometry of these new clicked 1,2,3-triazoles was explored by density functional theory (DFT) using the B3LYP/6-311++G(d,p) level; also, the potential activity of the compounds for light absorption was simulated by time-dependent DFT calculations (TD-DFT). The antitumor impacts of the newly synthesized compounds were in vitro estimated to be towards the human liver cancer cell line (HepG-2), the human colon cancer cell line (HCT-116), and human breast adenocarcinoma (MCF-7). Among the tested compounds, conjugate 7 was the most potent cytotoxic candidate towards HepG-2, HCT-116, and MCF-7, with IC₅₀ = 12.22, 14.16, and 14.64 µM, respectively, in comparison to that exhibited by the standard drug doxorubicin (IC₅₀ = 11.21, 12.46, and 13.45 µM). Finally, a molecular docking study was conducted within the epidermal growth factor receptor (EGFR) active site to suggest possible binding modes. Hence, it could conceivably be hypothesized that analogies 7, 6, and 5 could be considered as decent lead candidate compounds for anticancer agents.

A new group of 1-phenylpyrazolo[3,4-d]pyrimidine derivatives 14a–d–21 were synthesized from 2-(6-methyl-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4-yloxy)acetohydrazide (12). All the synthesized compounds were evaluated for their cyclooxygenase (COX) inhibition, anti-inflammatory activity and ulcerogenic liability. All the target compounds were more potential in inhibiting COX-2 than COX-1. Compounds having pyrazolyl moiety in a hybrid structure with pyrazolo[3,4-d]pyrimidine scaffold (14a–d, 16 and 17) showed higher edema inhibition percentage activities (34–68%) and the 5-aminopyrazole derivative (14c, ED₅₀=87.9 μmol/kg) was the most potent one > celecoxib (ED₅₀=91.9 μmol/kg). While, the in vivo potent compounds (14a–d, 16, 17 and 21) caused variable ulceration effect (ulcer index= 0.33–4.0) comparable to that of celecoxib (ulcer index= 0.33), the pyrazol-3-one derivative (16) and the acetohydrazide (21) were the least ulcerogenic derivatives showing the same ulcerogenic potential of celecoxib.

Selective inhibition of cyclooxygenase-2 (COX-2) isozyme afforded a useful drug design concept that resulted in the development of effective anti-inflammatory drugs that are devoid of adverse side effects, in particular gastrointestinal irritation, ulcerogenicity and renal toxicity attributed to inhibition of the cytoprotective cyclooxygenase-1 (COX-1) isozyme. Unfortunately, some selective COX-2 inhibitory drugs such as rofecoxib and valdecoxib are believed to be responsible for cardiovascular complications. Nitric oxide (NO) is an effective vasodilator that also inhibits platelet aggregation. Therefore hybrid NSAIDs containing NO-donor moieties have been developed to obtain effective treatment of inflammation with reduced GI and cardiovascular side effects. Here we review some of the most promising recent advances in NO-NAISDs donor drug development and summarizes medicinal chemistry efforts in search for new NO-NSAIDs prodrugs in an attempt to pave the way for further development in this promising area of research.