Cycloadditionen. 24. Synthese und Reaktionen vonsec. N-Aryl-buta-2,3-dien-amiden
摘要:
The reaction of aryl isocyanates (1) with allenyl magnesium bromide(2) furnishes the sec. N-aryl-3-butynamides (4), which tend to tautomerize to the 2,3-butadienamides (5). Further heating of 5a-f (bearing benzoid nuclei) leads to decompositon, only 5g (bearing the naphthyl group) undergoes the expected intramolecular Diels-Alder (IMDA) reaction, leading to the benzo-tricycle (7g). By reaction of a second molecule isocyanate 1 the carbamoylation of the NH moiety of 5a, c and of 3g and 4g, resp. takes place. The thereby formed N-aryl-N-butadienoyl ureas (9) either cyclize to furnish the the N-carbamoyl-2-quinolones (10) or undergo the IMDA-reaction leading to the tricyclic compounds (11). The N-butadienoyl-N-(1-naphthyl)ureas (12) only furnish the IMDA-benzo-tricycles (13).
[EN] ALLENAMIDE AS AN ORTHOGONAL HANDLE FOR SELECTIVE MODIFICATION OF CYSTEINE IN PEPTIDES AND PROTEINS [FR] ALLÉNAMIDE FORMANT POIGNÉE ORTHOGONALE POUR UNE MODIFICATION SÉLECTIVE DE LA CYSTÉINE DANS DES PEPTIDES ET DES PROTÉINES