guanidyl

Guanidyl is a functional group in organic chemistry with the chemical formula (NH2)2C=NH. It is characterized by a central carbon atom double-bonded to one nitrogen atom and single-bonded to two other nitrogen atoms. These nitrogen atoms are typically part of amino groups, making guanidyl a derivative of guanidine. The guanidyl group is a basic moiety due to the delocalization of positive charge within the C-N system, which stabilizes the protonated form. This basicity is a key feature of many compounds containing the guanidyl group.

The guanidyl group is found in several biologically important molecules. Perhaps the most well-known example is arginine, an essential amino acid. The guanidyl group in arginine plays a crucial role in its chemical properties, including its ability to form salt bridges and hydrogen bonds. Another significant compound containing this group is creatine, involved in energy metabolism in muscle tissue. The guanidyl group is also present in various alkaloids and pharmaceuticals, contributing to their biological activity. Its synthesis often involves reactions with cyanamide or urea derivatives. The presence of the guanidyl group can influence a molecule's solubility, reactivity, and interactions with biological targets.