The hydrolysis of the spicamycin mixture (I) with R = alkyl by means of HCl in alcohol or water gives 6-(spicaminylamino)purine (II). (The hydrolysis can also be performed with other inorganic acids such as H2SO4 or organic ones such as acetic acid or formic acid.) The condensation of (II) with N-(tert-butoxycarbonyl)glycine (III) by the active ester method yields the protected glycyl derivative (IV), which is deprotected with TFA (or methanolic HCl) to afford the glycyl derivative (V). Finally, this compound is condensed with tetradeca-2(E),4(E)-dienoic acid (VI) by the active ester method to provide the target carboxamide derivative.