Phenyl isocyanate → 2-{3-[1-tert-Butoxycarbonyl-5-(4-trimethylstannanyl-benzylamino)-pentyl]-ureido}-pentanedioic acid di-tert-butyl ester

Participants

Reaction Steps

The following compounds of the general structure 8 were prepared in overall yields ranging from 20-60% by the route depicted in Scheme B. The key synthetic intermediate (4) was reacted with the appropriate phenylisocyanate at room temperature to afford the desired protected intermediates (5) in good yields. The t-butyl ester protecting groups were removed in the presence of 50% TFA in DCM for 1 hour at room temperature. Upon completion, the reactions were concentrated on a rotary evaporator purified by HPLC or recrystallization to afford the desired products (6) in 40-90% yield.

Provenance & Evidence