Table 2. Inverted selectivity of derivatisation of MeDAP. Formation of the six-membered aminal ring by the condensation with PYRAL leaves only the terminal amino group available for the reaction with electrophiles. Isolated yields for one pot multi-step procedures. Boc-PheOSu = N-t-butyloxycarbonyl-phenylalanine-N′-hydroxysuccinimide ester; CbzCl = benzyl chloroformate.

Ref.	Reagent 1	Reagent 2	Solvent	Deprotecting agent	Yield
C1	PhNCO	—	CH3CN	BnONH3Cl	74%
C2	PhNCO	CbzCl	CH3CN	BnONH3Cl	74%
C3	PhNCO	Boc-PheOSu	CH3CN	BnONH3Cl	76%