[6453-62-9] · C16H15NO7 · 3,5-Dimethoxybenzyl 4-Nitrophenyl Carbonate · (MW 333.30)
(amino-protecting group used in peptide synthesis1)
Physical Data: mp 114-15 °C.
Solubility: sol chloroform, THF.
Preparative Method: by reduction of 3,5-dimethoxybenzoic acid with Lithium Aluminum Hydride and then acylation of the resulting 3,5-dimethoxybenzyl alcohol with 4-nitrophenyl chloroformate.1
Reaction of amino acids with the reagent (1) in aqueous THF in the presence of Sodium Hydroxide affords 3,5-dimethoxybenzyloxycarbonyl derivatives in 55-76% yields (eq 1).1 This protecting group can be cleaved by irradiation with a high-pressure mercury lamp for 1.5 h in aqueous dioxane (42-85% yields). The advantage is provided in that acidic, basic, or reductive reaction conditions can be avoided.
Eric D. Edstrom
Utah State University, Logan, UT, USA