ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Triethylamine-mediated condensation of S-benzylisothiouronium chloride with [~1-4-arylmethylene-Z-pheny~-2-oxazalin-5ones (4) in ethanol gives [Z)-2-amino-4-arylmethylene-2-imidazol-in-5-ones (11, whereas the similar reaction with 4-cyclohexylidene-Z-phenyl-Z-oxazalin-5-0ne[~) produces 5-benaoylamino-2-benzy-lthi0-6-oxo-4.4-~pir0~yclahexyl-1,4.5.6-tetrahydropyrimidine (5) which on aminolyses with arylamines affords the corresponding 2arylamino derivatives(l6).Counter-attack reagents1 are of considerable importance in synthetic organic chemistry, but their scope in many reactions does not seem to have been properly explored. With an appropriate choice of the substrates, reagents, and the reaction conditions, i t may be possible to carry out many multi-step syntheses in the same flask involving highly ordered conversions, resembling biochemical changes, follawing definite protocols. We propose to call such transformations as "disciplined reactions'' and in this article present a navel one-pot synthesis a f the title campaundsI~1 and (151, using the reactions of 4-arylmethylene-2-phenyl-2-oxazolin-5-ones(41and 4 -c y c l o h e x y l i d e n e -2 -p h e n y 1 -2 -o x a z o l i~] , respectively, with S -b e n z y l i~~t h i o~r~n i~m chloride[E) in ethanol containing triethylamine. -It should be noted that several 2-aminoimidazole alkaloids have Deen isolated from marine sponges. 2-5 Some o f these, for example aplysinopsin-type alkaloids [L~.4.5 which contain a 3-indolylmethylene group at the 4[51-position of the imidazole ring, have generated interest because of their reported cytotaxicity against cancer and for affecting neurotransmission. These compounds are related to creatinine, an important end product of nitrogen metabolism in human beings, which belongs t o a class of heterocycles called gly~ocyamidines.~'~The stereochemistry of aplysinapsin-type alkaloids (11 has been investigated and it has been found that the configuration at the olefinic centre depends on the Substituent present in the m~l e c u l e .~'~T h e stable isomers were amenable to phota-i~omerisation to the less stable isomers which in turn were thermolabile. Synthesis o f 1 was carried out by the condensation o f indole-3-carboxaldehyde (i,Y=01 with the corresponding 2-iminoimidaaolidin-5-0nes[?l.~ In our approach. (21-4-[3indolylrnethylene]-2-phenyl-Z-oxazalin-5-ane ( 5 ) was used as a substrate and when heated with 6 in ethanol in the presence of triethylamine furnished a sulphurfree compound which has been characterised as 2-amino-4-(3-indolylmethylenel-2imidazolin-5-one ( G I on the basis o f its spectral data and chemical reactions.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.