Abstract: Synthetic compounds combining sulphur-containing or sulphur-free amino acids with aminopyrimidine and aminopyridine derivatives, as well as mineral or organic acid addition salts produced in the presence of an amino grouping, were synthesized. Non-sulphur amino acids such as glutamic acid, pyroglutamic acid, tyrosine, histidine and arginine, and sulphur amino acids such as methionine, cysteine, S-methyl-cysteine and cystine, were attached to minoxidil to give monosubstituted and disubstituted derivatives. The amides with a pyrimidine or pyridine structure coupled to an amide structure in which the carbonyl is from sulphur-containing or sulphur-free amino acid have the properties of; (1) excellent adhesion to the skin, particularly the epidermis; (2) capturing free radicals, in particular the superoxide anion and the hydroxyl radical; (3) selectively relaxing smooth muscle fibers; and (4) in vitro and in vivo keratinocyte growth, hair growth in humans, and fresh and accelerated fur growth in animals.