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 An infrared study of rotational isomerism in thiazole-2-carboxylates, published in 1981-08-31, which mentions a compound: 79247-77-1, Name is 5-Bromo-4-methyl-thiazol-2-ylamine hydrobromide, Molecular C4H6Br2N2S, HPLC of Formula: 79247-77-1.
Twenty-five alkyl thiazole-2-carboxylates with a range of 4- and 5-substituents were prepared through the Hantzsch synthesis. E.g., cyclocondensation reaction of (H2N)2CS with MeCOCH2Br followed by bromination, oxidation, and alkylation gave the thiazole esters I (R = Me, Et). Solutions of these esters show well resolved doublets in the carbonyl IR spectra, due to rotational isomers. The higher wave number components were assigned to the more polar carbonyl O,S-anti-s-trans rotamers and those at lower wave number to the O,S-syn-s-trans forms. Small, but systematic, differences between the Me esters were noted.
Different reactions of this compound(5-Bromo-4-methyl-thiazol-2-ylamine hydrobromide)HPLC of Formula: 79247-77-1 require different conditions, so the reaction conditions are very important.
Reference:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics