In general, if the atoms that make up the ring contain heteroatoms, such rings become heterocycles, and organic compounds containing heterocycles are called heterocyclic compounds. An article called Comparison of enzymic semisyntheses of peptide amides: human growth hormone releasing factor and analogs, published in 1991, which mentions a compound: 10466-61-2, Name is H-Leu-NH2.HCl, Molecular C6H15ClN2O, Reference of H-Leu-NH2.HCl.
Enzymic semisyntheses of growth hormone releasing factor (GRF), a 44-residue peptide amide hormone, from C-terminal acid precursors are compared. A recombinant α-amidating enzyme was used to convert the glycine-extended precursor, GRF(1-44)-Gly-OH, to GRF(1-44)-NH2 in an essentially quant. fashion). Trypsin was used to convert the precursors, GRF(1-43)-OH and GRF(1-44)-OH, to GRF(1-44)-NH2 (60 and 15% conversion, resp.) in a 75% (v:v) aqueous AcNMe2 containing a large excess of leucine amide. Carboxypeptidase Y-catalyzed transpeptidations of the precursors GRF(1-44)-OH and [Ala44]-GRF(1-44)-OH to GRF(1-44)-NH2 in aqueous leucine amide solutions were also attempted. The trypsin-catalyzed direct amidation of [Ala15]-GRF(1-29)-OH in concentrated ammonium acetate/ammonia buffer (95%, 1,4-butanediol cosolvent) to form the superactive analog [Ala15]-GRF(1-29)-NH2 (ca. 25% conversion at equilibrium) is also described.
There are many compounds similar to this compound(10466-61-2)Reference of H-Leu-NH2.HCl. if you want to know more, you can check out my other articles. I hope it will help you，maybe you’ll find some useful information.