Asymmetrical synthesis of lysine derivatives

Conclusions The stereoselective aminolysis of the azlactone of DL-diacetyllysine by the action of S--phenylethylamine in t-BuOH leads to an excess of the SS-diastereomer of the -phenylethylamine or diaceyllysine. Crystallization of the mixture of diastereomeric amides gave the optically pure S--phenylethylamide of S-diacetyllysine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 925–927, April, 1986.     

A new indolizidine synthesis

The intramolecular 1,6 Michael type addition of a primary amine to an electrophilic diene occurs under very mild conditions; it is the key step for a new preparation of indolizidines.     

A new sulfene synthesis

Treatment of trimethylsilylmethanesulfonyl chloride with cesium fluoride in acetonitrile at room temperature has been found to produce sulfene which can be trapped in good yield.     

A new tetrahydroisoquinoline synthesis

Cyclization of 2-vinylbenzylamines affords 1,2,3,4-tetrahydroisoquinolines. The synthesis of the vinylbenzylamines from benzhydrols or isoindolones is described.     

A new synthesis of phenylvinylselenides

Ketonic hydrazones react smoothly at room temperature in tetrahydrofuran in presence of an excess of $\text{t}$-butyltetramethylguanidine with phenylselenenyl bromide to give good to excellent yields of phenylvinylselenides.     

A new synthesis of pyrroles

The radical reaction between an N-ethylsulfonylenamide and an alpha-xanthyl ketone gives an intermediate gamma-keto imine which spontaneously ring-closes to the pyrrole.     

A new synthesis of tanikolide

We report a concise synthesis of tanikolide 1, which was obtained from ethyl 2-oxocyclopentanecarboxylate in four steps: alkylation, Baeyer-Villiger reaction, saponification, and reduction/lactonization, in 70% overall yield. Our strategy should be suitable for the preparation of 1 in multigram or larger quantities. The net result of the last two steps (i.e. saponification and reduction/lactonization) is an efficient reduction of the ethoxycarbonyl of 3 while keeping the lactone carbonyl intact.     

A new synthesis of oxazoles

Oxazoles are prepared from the ketoximes in a single pot sequence.     

A new synthesis of s-triazines

The unions of urea, guanidine, thiourea, biguanide, and biuret were reacted with aromatic nitriles to yield s-triazines. Ortho-chloro substituted aromatic nitriles gave other products or did not react because of steric factors.     

A new synthesis of fuscin

The prenylation of trihydroxylacton (6) with prenyl bromide in the presence of silver oxide yields mainly the C-prenyl derivative with good yield. The intermediate 7 thus obtained is cyclised to dihydrofuscin with formic acid.     

A new synthesis of chlorins

A new synthesis of chlorins has been developed, based upon the acid-catalyzed condensation of dialdehydes AB with dipyrromethanes CD.     

A new synthesis of phthalimidines

A new synthesis of phthalimidines is described. 3-Acyloxy-2-aryl- and 2-acylamino-3-acyloxyphthalimidines were prepared by the reaction of 3-arylaminophthalides or o-formylbenzoic acid acylhydrazones with acetic or propionic anhydrides. Their reactions with O-, N-, S-, and C-nucleophiles were studied. The structure of 2-acetyl(cyanoacetyl)amino-3-acetoxyindolin-1-one was confirmed by X-ray diffraction analysis.     

A new synthesis of methanoisoindoles

Russian Journal of Organic Chemistry -     

A new synthesis of hydroxyphthalides

Cyclization of suitable enamino ketones can produce hydroxyphthalides.