Novel 1,5-benzothiazepin-4-(5H)-one derivatives (8a-8g) have been synthesized by intramolecular cyclization of 6 using propyl phosphonic anhydride (T3P) as a cyclodehydrating agent. The anti-angiogenic and anti-oxidant properties of the new derivatives were then evaluated. Compounds 8b, 8d, 8e, 8f and 8g exhibited very good inhibition of capillary proliferation, thus proving their anti-angiogenic properties. In addition, the in vitro antioxidant activities of these compounds were evaluated using diphenyl picryl hydrazine (DPPH), OH-, metal ion-chelating and NO (nitric oxide) assays, and the results compared with butylated hydroxytoluene (BHT), a well known anti-oxidant. Compounds 8a-8g showed excellent free-radical scavenging activities in the metal ion-chelating assay, and compounds 8f and 8g showed nitric oxide radical scavenging properties at a concentration of 20-100 µg/mL, and are thus more potent than BHT.

The process of racemisation of atropisomeric biaryls was modelled by means of DFT calculations at an advanced B3LYP/6-31G* theoretical level. Thus, the detailed protocol of determination of the racemisation rate presented herein provides a practical prediction tool for elucidation of the configurational stability of atropisomers.

This study was aimed at highly stereoselective ring-opening of epoxides with acetic anhydride in the presence of molecular sieves 4Å as an efficient reagent. Yields of the 1,2-diacetates are uniformly good to excellent and the reagent may be recycled without the requirement for purification. High yields, short reaction times, ease of preparation and simple work-up procedure (filtration) are advantages of this method.

A new and simple synthetic methodology for the preparation of 3-arylpyrimido[4,5-c]pyridazine-5,7(6H,8H)-diones and 3-aryl-5-oxo-7-thioxo-7,8-dihydropyrimido[4,5-c]pyridazin-5(6H)-ones by a one-pot three component reaction of barbituric acid or thiobarbituric acid with arylglyoxals in the presence of catalytic amount of ZrOCl2∙8H2O as green Lewis acid and hydrazine hydrate at ambient temperature in water was reported. All of these pyrimidopyridazines derivatives have one clustered water molecule in their molecular structure. The use of ZrOCl2∙8H2O catalyst is feasible because of its easy availability, convenient handling, high stability, simple recovery, reusability, good activity and eco-friendly.

Indium (III) chloride (InCl3) and metaphosphoric acid ((HPO3)n) were found to be efficient and recyclable catalysts for the synthesis of 1,8-dioxooctahydroxanthene derivatives as biologically important molecules in high turnover numbers and rates. Several substituted xanthenes can be prepared in high yield and purity by direct reaction of cyclic B-diketones and aldehyde derivatives in the presence of a catalytic amount of InCl3 and (HPO3)n as Lewis acids and at ambient temperature under solvent-free conditions. This newly reported procedure profit some advantages such as short reaction times, high yields of products, cheap, easy to use, facile practical conditions, and wholesome with green chemistry without using harmful solvents.

A simple, efficient and green one-pot, four-component synthesis of highly substituted polyhydronaphthalenes in aqueous media is described. The method has such advantages as short reaction times, high yields, mild reaction conditions, operational simplicity and environmentally benign.

This study investigated the selective synthesis of aryl-bis(2-hydroxy-1-naphthyl)methane for the first time under microwave irradiation in solvent-free medium within 5 min using 10 mol % of B(HSO4)3 (BSA) as reusable solid acid catalyst. The same reaction could also be conducted at 90-100 °C in neat for the formation of alkyl or aryl 14H-dibenzoxanthenes in presence of BSA catalyst with excellent yields.

Experimental and computational approaches were used to estimate the lipophilicity of novel 1,2,4-triazole derivatives. These derivatives have been subjected to this research, because they exhibit antimicrobial activity. The chromatographic analysis of RP-HPLC and RP-TLC was carried out using methanol-water or acetonitrile-water as mobile phase. The linear relationships between logk (or R_M) values and the concentration of organic modifier were obtained. The lipophilicity was expressed as chromatographically derived descriptors: ?logk?_W, S, ?0 and scores logk and R_Mcorresponding to the first principal component. The experimental lipophilicity data have been compared with the computer calculated lipophilicity parameters (milogP, clogP, ALOGPs, AClogP, AlogP, MLOGP, KOWWIN, XLOGP2, XLOGP3, ?logP?_ChS) of the same molecules. The matrices were created with ?logk?_W or R_M^0and logP and they have been the subject of PCA analysis.

Selective oxidation of primary and secondary alcohols to the corresponding aldehydes and ketones was achieved efficiently using K2S2O8/activated charcoal system. All reactions were carried out at solvent?free conditions (40?45 ?C) within 15?60 min to give the products in high to excellent yields.