Procédé de préparation de composés d'intérêt par cyclisation intramoléculaire et formation d'un pont éther biaryl

Novel method for intermolecular cyclization by formation of a biaryl ether bridge through the reaction as shown above. In formulas (I) and (II) R1 is a nitro radical adjacent to the oxygen bridge, Hal is a fluoride or chlorine atom, R2, R3 and R4 together form a peptidic chain, in the presence of a weak phase in a heterogeneous medium. The invention also concerns compounds of formulas (I) and (II) and the use of compounds of formula (I) to obtain useful compounds

Palladium catalyzed reductive deprotection of alloc: Transprotection and peptide bond formation

N-allyloxycarbonyl group could be efficiently removed using sodium borohydride as hydride donor in the presence of catalytic amount of palladium (0). The conditions were applied to chemoselective protecting group transformation (transprotection) and peptide bond formation