Three anthraquinones, the well known emodin (3) and physcion (6) and the new anthraquinone glycoside emodin-8-β-D-idopyranoside (7) were isolated from leaves of Muehlenbeckia hastulata. The antioxidant activity of these compounds was measured using the DPPH assay; all three showed weaker antioxidant activity than gallic acid.

The reaction of 1‐substituted‐3‐methylpyrazol‐5‐ones 1 with alkyl chloroformates and calcium hydroxide in dioxane have been studied. With 1‐phenyl‐3‐methylpyrazol‐5‐one, the isolated product was alkyl 3‐methyl‐5‐oxo‐1‐phenylpyrazole‐4‐carboxylate 2 but with 1‐alkyl‐3‐methylpyrazol‐5‐one formation of 1‐alkyl‐5‐alkoxycarbonyloxy‐3‐methylpyrazole 3 was observed. Replacement of alkyl chloroformate by bis(alkoxythiocarbonyl) sulfide results in the formation of 4‐alkoxythiocarbonyl derivatives 4 in low yield with both 1‐substituted‐3‐methylpyrazol‐5‐ones.

The metal chelates formed by 4-alkylcarboxylate, 4-alkoxythiocarboxylate and 4-alkyldithiocarboxylate derivatives of l-phenyl-3-methyl-2-pyrazolin-5-one with copper(I1) and uranium(V1) have prepared. The complexes were characterized by elemental analyses, IR, UV and ' H NMR spectral studies. All the complexes have a metal : ligand ratio of 1:2.