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The reaction of acetanilide (1) with nitrobenzene (2) in the presence of a base in DMSO yielded p -nitrosodiphenylamine (3) as the major product. This unusual regioselective formation of the deoxygenated product 3 has been rationalized in terms of solvent effects exerted by DMSO.

Photolysis of the enones 4a–c leads to regioselective hydrogen abstraction and subsequent cyclization to furnish the spiro compounds 5a–d, which on further elaboration provide the spiro dione 6, a model for the antitumour antibiotic, fredericamycin-A 1.

Synthesis of (±)heritol and epi -heritol is described. The key step is the osmylation of the unsaturated ester 9a. Osmylation is used as a tool to construct the α,β-unsaturated γ-lactone system.

Osmylation of β,γ-unsaturated esters and acid catalysed cyclisation of the resultant diols generate butenolides in high yields.

We report in this paper an high resolution (R s =2,5) HPLC method using a silica gel column and 50% watersaturated diethyl ether-n-hexane (25:75) as the mobile phase with detection at 280 nm for the determination of underivatized 2-naphthylamine in technical 1-napthtylamine with sub-ppm as the lower detection limit in n-hexane solution

A fast, efficient and reproducible method for the separation of the five major opium alkaloids by thin-layer chromatography coupled to flame ionization detection is reported. The alkaloids were separated without derivatization on silica rods of type SII using the partial scanning or peak pyrolysis method —where organic matter separated on the rods are burnt when they pass through the hydrogen flame— between the stages of a two-step development system. The first development, in benzene-acetonitrile-ethyl acetate (60:20:20, v/v) separated narcotine and papaverine. Morphine, codeine and thebaine were separated during the second development in ethyl acetate-benzene-acetonitrile-ammonium hydroxide (25:30:40:5, v/v). The best binary solvent system was benzene-ethanol (9.5:0.5, v/v) and (9:1, v/v) which separated all the five alkaloids simultaneously.

A novel synthesis of unsymmetrical azo aromatics inaccessible by diazo-coupling reaction is reported. The synthesis involved the reaction of acetanilides with nitroarenes under moderate reaction conditions. A reaction pathway via a nitrosoarene intermediate involving elimination of the elements of the acetate anion, is proposed.

An efficient, one pot strategy for the synthesis of spiro [4. n]dione and 2,2-disubstituted cyclopentane-1,3-dione has been developed by using ketals and 1,2-disilyloxycyclobutene in the presence of excess BF 3.Et2O.

Five 4-(2′-phenylisopropyl)phenol esters were synthesized and their properties as stationary phases in gas—liquid chromatography were investigated. Their McReynolds' constants were determined. To investigate their selectivity, different aromatic positional isomers were used as solutes. Quantitative analyses were carried out for some of these isomers. These new esters may offer some advantages for gas chromatography.

Acylation, benzoylation, toluylation and related reactions of active methylenes, e.g. indene, fluorene and diethylmalonic ester is enhanced by the use of solid-liquid phase transfer catalyst. An interesting rearrangement with phthaloyl chloride is reported under identical conditions.

Marschalk reaction of leucoquinizarin (2) with readily obtainable 4-bromo-2-acetoketal-1-butyraldehyde (3), from ethyl acetoacetate or acetone, gave in one step 4-demethoxy-7, 9-dideoxydaunomycinone (1a) in 60% yield.

The separation of the five principal alkaloids (morphine, codeine, thebaine, noscapine and papaverine), three minor alkaloids (laudanosine, cryptopine and narceine), meconic acid and some unidentified constituents in gum opium samples has been achieved on a reversed-phase phenyl column by gradient high-performance liquid chromatography using a simple and inexpensive mobile phase system. The linear gradient programme was started at 5% and ended at 70% methanol in triethylammonium phosphate buffer in 20 min. The five principal alkaloids were also determined with good precision. The method requires minimum sample preparation and is suitable for routine analysis.

A novel route to the model spiro-compound 4, for Fredericamycin A (1) is reported, which involves the use of PTC for activating indenyl anion nucleophilicity. A parallel photo-route to 4, from 9 and (or) 10 is described.