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The 1, 8-dihydroxyanthraquinones such as emodin (I), physcion (II), crysophanol (III), aloe-emodin (IV) and rhein (V) show reversible 2-electron reduction wave forming the hydroquinones in aqueous isopropanol solutions. Their semiquinones are stable in dimethylformamide. Sennosides (VI) show irreversible 2-electron reduction wave accompanied with 2 adsorption waves, which are ascribed to reductive cleavage of the C-C bridge to the anthrone (VII). The carbonyl in VII is successively reduced to the corresponding alcohol (XI), which seems to dehydrate to the anthracene (XII). Then, the I-V and VI in rhubarb can be determined by polarography.

8-Chloro-6-phenyl-4H-s-triazolo [4,3-a] [1,4] benzodiazepine (D-40TA)-1-14C (V-14C) was synthesized by the reaction of formic acid-14C with 7-chloro-2-hydrazino-5-phenyl-3H-1, 4-benzodiazepine in the presence of N,N′-carbonylbis (2-methylimidazole). The overall radio-chemical yield from formic acid-14C was 57.8%.

Stabilities of 3-morpholinosydnonimine (II), hydrochloride (I) and N-ethoxycarbonyl-3-morpholinosydnonimine (VIII) were examined by photometry, potentiometry, thin-layer chromatography and spectroscopy. In alkaline solution VIII goes to ethanol, carbon dioxide and II, which successively decomposes to N-morpholino-N-nitrosoaminoacetic acid (V) and N-cyanomethylenaminomorpholine (VI) via N-morpholino-N-nitrosoaminoacetonitrile (III). In the processes of I=II=III, the initial equilibrium is very rapid and the consecutive cleavage is a spontaneous first order reaction at pH 3-7 or a base catalyzed reaction at pH 8-10. The initial process of is a base catalyzed. first order hydrolysis of N-ethoxycarbonyl group. Hydrolyses of I and VII in hydrochloric acid form morpholine, nitrogen, chloroacetic acid and ammonium chloride. Photolyses of I and VII in acid solution at γ

Electrochemical reduction of cephalosporanic acid derivatives (I) bearing various substituents at the 3-position gave the corresponding 3-methylenecepham derivatives (II), a new class of cephalosporins. Reductive opening of the 3-hydroxymethyl-3-cephem-4-carboxylic acid lactone (IV) was effected to give (II) by cathodic reaction. The 3-methylenecepham derivatives (II) were readily isomerized to the 3-methyl-3-cephem derivatives (III) providing a new synthesis of cephalexin [7-(D-2-amino-2-phenylacetamido)-3-methyl-3-cephem-4-carboxylic acid](IIIc). The reaction mechanism is discussed on the basis of deuteriation and polarography of the cephalosporins involved.