Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown excellent antimicrobial, antiviral, antidiabetic, anti-melanogenic, anti-ulcer, anticancer, anti-mycobacterial, anti-inflammatory, DNA binding and chemosensing activities. In the present review, the above-mentioned activities of the nitrogen-containing heterocyclic compounds (pyridines), hydroxyl (phenols) and azo derivatives are discussed with reference to the minimum inhibitory concentration and structure–activity relationship, which clearly indicate that the presence of nitrogen in the phenyl ring; in addition, the hydroxyl substituent and the incorporation of a diazo group is crucial for the improved efficacies of the compounds in probing different diseases. The comparison was made with the reported drugs and new synthetic derivatives that showed recent therapeutic perspectives made in the last five years.

The present study is aimed at adsorptive removal of Mercury (Hg²⁺) using highly functionalized nanomaterials based on Graphene Oxide Zeolitic Imidazolate Framework composite (ZIF-67@GO). Solvothermal methodology was used to synthesize ZIF-67@GO composite. Synthesized compounds were confirmed by FTIR, SEM, PXRD and EDX analysis. The as-prepared ZIF-67@GO was tested as efficient adsorbent for effective removal of Mercury (Hg²⁺) from aquatic environment. The atomic adsorption spectrophotometer was used to monitor the process of adsorption of Hg⁺² on ZIF-67@GO. From the adsorption data, the maximum removal efficiency achieved was 91.1% using 10 mg amount of composite for 50 mL using 20 ppm Mercury (Hg²⁺) solution. Different parameters like pH, contact time, concentration, adsorption kinetics and isotherm were also examined to explore adsorption process. Adsorption data fitted well for Freundlich Model having R² value of 0.9925 than Langmuir Isotherm with R² value of 0.9238. Kinetics were rapid and excellently described via 2nd order model with R² = 0.99946 than 1st order model with R² value of 0.8836. Freundlich and pseudo 2nd order models validated that multilayer chemisorption occurs during adsorption process due to the presence of highly functionalized sites on ZIF-67@GO composite. The synthesized composite material has shown excellent reusability. Thus, water stable ZIF-67@GO composites can efficiently be used for Mercury (Hg²⁺) confiscation from water.

In this paper, the facile synthesis of graphene oxide and MOF based composite material for the demanded adsorption of leading antibiotic is reported. The adsorbent showed good results for removal of norfloxacin with high adsorption capacity (1114.82 mg/g) and removal efficiency (93.61 %). In addition, Langmuir model proved most suitable with highest value of R² = 0.99929 among three applied isothermal models. The thermodynamic study showed spontaneous and exothermic (ΔH = −1.1×10⁻⁵ Kj/ mol, ΔG = −13324.33 Kj/ mol) nature of adsorption process with reusability of 88.4 % after several cycles. Moreover, statistical analysis and mechanistic study were also performed.

In the present study, highly water stable polymeric metallo organic composite (PMOC) has been synthesized and incorporated into water solution for selective adsorption study. For elucidation of structure, FTIR, P-XRD, SEM, and BET techniques were applied. Several factors related to water chemistry and adsorption analysis were also investigated. The maximum adsorption capacity was 1271.33 and 157.11 mg/g for Pb(II) and As(V), respectively. Chemisorption, monolayer adsorption and homogeneous adsorption takes place for adsorptive confiscation of these metals as studied from kinetics. From consequences, it was established that increase in number of active sites can dramatically increase the adsorption capacity of adsorbent.