Wide range of 2,4,5-trisubstituted imidazoles were synthesized using eco-friendly, readily available, inexpensive Zn(OAc)2•2H2O (5 mol%) under solvent-free conditions in moderate to excellent yields by condensation from aldehyde, ammonium acetate and benzil at 70 0C. The optimized reaction parameters were successfully applied for the synthesis of divergent 1,2,4,5-tetrasubstitued imidazoles using aromatic amine as fourth component. All the imidazole derivatives were sufficiently characterized by IR, NMR and Mass spectral analyses.

A new series of 2-[3-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-4-pyrazolyl]-3-aryl-1,3-thiazolan-4-one 5(a-i) have been designed, synthesized and evaluated for their in vitro antibacterial activity against Gram positive bacteria viz. Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 6538p), Micrococcus luteus (IFC 12708) and Gram negative bacteria viz. Proteus vulgaris (ATCC 3851), Salmonella typhimurium (ATCC 14028), Escherichia coli (ATCC 25922) the antifungal activity against Candida albicans (ATCC 10231), Aspergillus fumigatus (HIC 6094), Trichophyton rubrum (IFO 9185), Trichophyton mentagrophytes (IFO 40996). Antibacterial evaluation indicates that compounds containing 4-methoxyphenyl 5c, 4-fluorophenyl 5d and 2,5-difluorophenyl 5h groups on thiazolidinone ring showed significant activity equal to that of standard drug. The antifungal evaluation shows that compound 5c is highly active against A. fumigatus, compound 5d and 5h were also active against C. albicans and A. fumigatus.

New series of fused 1,2,4-triazoles, i.e., 3-(4-isopropylphenyl)-6-substituted phenyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles (5a-5j) have been synthesized via a four-step procedure and using eco-friendly reaction condition at some steps of the synthesis. It was adopted by the formation of hydrazide of methyl 4-isopropylbenzoate (1) followed by reaction with CS2 in basic media to afford potassium salt, which on cyclized to our essential step, 4-amino-5-(4-isopropylphenyl)-4H-1,2,4-triazole-3-thiol (4). The desired adducts (5a-5j) were formed by (4) on reaction with various aromatic acids in POCl3 media. The newly synthesized triazolo- thiadiazoles have been characterized by different spectroscopic techniques and investigated for their in vitro antibacterial and antifungal activity. It was revealed that the compounds 5a, 5c, 5h, and 5i showed interesting antibacterial and antifungal activity compared to the used reference standard.

A new series of 4-amino-4H-1,2,4-triazole derivatives, 3a-f and 5a-f were synthesized by using various aryl aldehydes and ketones. FT-IR, ¹H NMR, ¹³C NMR and mass spectral studies were characteristic of the synthesized compounds. These new compounds were screened in male wistar rats and compared with the standard drug for their anticonvulsant activity against maximal electroshock seizure (MES) model. Compounds 3b and 5d of this sequence were found to be the most active. The same compound did not demonstrate neurotoxicity at the administered maximum dose (100 mg / kg) and these compounds showed good protection compared to other compounds.

The interaction of (2-aryl-5-(hydroxyalkylamino)-1,3-oxazol-4-yl)phosphonates with hydrogen chloride, hydrogen iodide and hydrogen thiocyanate in anhydrous medium led to formation of new phosphorylated peptidomimetics containing C-terminal ω-haloalkyl and ω-thiocyanoethyl residues.

The space-time model combines spatial and temporal elements. One example is the Generalized Space-Time Autoregressive (GSTAR) Model, which improves the Space-Time Autoregressive (STAR) model. The GSTAR model assumes that each location has heterogeneity characteristics, and that the data is stationary. In this research, the moving average component is calculated by involving the relationship between variable values at a certain time and residual values at a previous time, and it is assumed that the data is not stationary, so the model used is the Generalized Space-Time Autoregressive Integrated Moving Average (GSTARIMA) Model. The model order for GSTARIMA is determined through the Space-Time Autocorrelation Function (STACF) and Space-Time Partial Autocorrelation Function (STPACF) to ensure accurate forecasting. Previous research only discussed the GSTARIMA(1,1,1) model, so in this research, the GSTARIMA(3,1,1) model will be addressed as a form of development of the GSTARIMA(1,1,1) model and applied to climate data. The climate data used in this research is sourced from NASA POWER and consists of rainfall variables with large data sizes, requiring the use of the data analytics lifecycle method to analyse Big Data. The lifecycle includes six phases: discovery, data preparation, model planning, model building, communicating results, and operationalization. Based on the data processing results with Python software, the GSTARIMA(3,1,1) model has a MAPE value of 9% for out-sample data and 11% for in-sample data. In contrast, the GSTARIMA(1,1,1) model has a MAPE value of 11% for out-sample data and 12% for in-sample data. So the GSTARIMA(3,1,1) model provides more accurate forecasting results. Therefore, selecting the correct model order is crucial for accurate forecasting.

Reaction of methyl 2-aryl-5-(chlorosulfonyl)-1,3-oxazole-4-carboxylates with 1H-pyrazol-5-amines and 1H-1,2,4-triazol-5-amines proceeds with the participation of endocyclic aminoazole nitrogen atoms to yield products containing a primary amino group. Being treated by sodium hydride these products undergo a further transformation into the tricyclic compounds. It has been shown that the cyclocondensation pathway includes the Smiles rearrangement with extrusion of SO2 followed by the elimination of MeOH. This reaction sequence is a convenient approach to the synthesis of new annulated [1,3]oxazolo[5,4-d]pyrimidine derivatives.

The reaction of lithiation of 2-bromo-4-(1,3-dioxolan-2-yl)-1,3-thiazole with in position 5 of the thiazole ring and double lithiation with t-butyllithium (t-BuLi) in positions 2 and 5 lithium diisopropylamide (LDA) are investigated. When lithiated and dilithiated thiazoles were treated with different electrophiles, a number of trifunctional 1,3-thiazoles were obtained with high yields.

Readily available tetrachloro-2-aza-1,3-butadienes enter into directed cyclocondensation reaction with N-phenyl-1,2-cyclopentanediamine which leads to regioselective cyclopentane annulation by the 1,3,5-triazepine. The formation of the 1,3,5-triazepine derivatives was confirmed proved by 1H- and 13C-NMR spectral study, elemental analysis and, in one case, single-crystal x-ray crystallographic study.

This paper summarizes the reaction of DABCO with the enol tosylate derivatives made from (L-Ser-L-Ser) and (L-Phe-L-Ser) diketopiperazines (DKP’s). The reaction between DABCO and EE-di-tosylate (L-Ser-L-Ser) DKP (2), results in the isomerization of the serine di-tosylate from EE-2 to ZZ-2. This is the first direct example of the utility of DABCO as a reagent demonstrating the successful isomerization in a DKP derivative. The E-enol tosylate of (L-Phe-L-Ser) DKP (4) upon reaction with DABCO provided a unique bis-ylidiene product (5).