The secondary metabolites isolated from Rubia species, their biological activities, and colouration properties have been reviewed. Over 150 chemical constituents belonging to different classes of bioactive compounds such as anthraquinones and their glycosides, naphthoquinones and glycosides, terpenes, bicyclic hexapeptides, iridoids, and carbohydrates are listed together with their source(s) and corresponding references.

Tellurium and selenium incorporated 5,10,15,20-meso-unsubstituted-21,23-ditellura/diselena coremodified porphyrinogens (N 2 Te 2 and N 2 Se 2 ), 5,10,15,20-meso-unsubstituted-21-tellura/selena coremodified porphyrinogens (N 3 Te and N 3 Se) and fully substituted meso-carbons porphyrinogens (N 2 Te 2 , N 2 Se 2 and higher analogs) are synthesized by 3 + 1 condensation of tellurophene/ selenophene dipyrranes and their corresponding diols in the presence of BF 3 -etharate or BF 3methanol. The meso-unsubstituted and substituted porphyrinogens were oxidized with chloranil/0.1% aqueous FeCl 3 in CHCl 3 at room temperature to obtain the corresponding porphines and porphyrins which are further reduced to corresponding chlorin and bacteriochlorin, whereas the fully mesosubstituted porphyrinogens were found to be good ligands for Hg 2+ . The structures of the products were characterized by IR, 1 H, 13 C, 125 Te, 77 Se NMR, CHN analysis, mass spectrometry and singlecrystal XRD.

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Graphite oxide and graphene oxides have been used as solid catalysts for the synthesis of 5,5-dialkyldipyrromethanes and calix[4]pyrroles in organic and aqueous solutions at room temperature.

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The synthesis of certain specifically 15N, 13C, and 2H isotope labeled l-(2-chloroethyl)-3-alkyl-l-nitrosoureas (CENUs) is described. Spectroscopic examination of CENUs and their isotope-labeled counterparts by , 16N, and 13C NMR and infrared spectra indicates that they adopt preferred conformations in nonpolar aprotic solvents in which the NO group is aligned toward the 2-chloroethyl group. The result is in accord with the conformation of MeCCNU in the crystalline state derived from X-ray diffraction. The chemical shifts and coupling constants in the CENUs change with both solvent polarity and basicity.

An efficient procedure for catalyst solubility, recycling and easy product isolation in oxidation of thiols to disulfides with molecular oxygen catalyzed by cobalt(II) phthalocyanines dissolved in ionic liquid at room temperature is reported.