ok guys.. finally i could get the IUPAC names of these molecules. here it is just in case anybody is interested.
a) tert-butyl 2-(2-(tert-butoxycarbonyl)aminoethyl)aminoethylcarbamate
b) tert-butyl 2-((2-(tert-butoxycarbonyl)aminoethyl)(3-bromopropyl)amino) ethylcarbamate