Bivalirudin Bivalirudin Bivalirudin (Angiomax or Angiox, manufactured by The Medicines Company) is a direct thrombin inhibitor (DTI). Chemically, it is a synthetic congener of the naturally occurring drug hirudin (found in the saliva of the medicinal leech "Hirudo medicinalis"). Bivalirudin is a DTI that overcomes many limitations seen with indirect thrombin inhibitors, such as heparin. Bivalirudin is a short, synthetic peptide. It is a potent and highly specific inhibitor of thrombin. It inhibits both circulating and clot-bound thrombin, while also inhibiting thrombin-mediated platelet activation and aggregation. Bivalirudin has a quick onset of action and a short half-life. It does not bind
Peptide bond by conformational strain as the peptide/protein folds into the native structure. This non-enzymatic process is thus not accelerated by transition state stabilization, but rather by ground state destabilization. The wavelength of absorption A for a peptide bond is 190–230 nm (which makes it particularly susceptible to UV radiation). Significant delocalisation of the lone pair of electrons on the nitrogen atom gives the group a partial double bond character. The partial double bond renders the amide group planar, occurring in either the cis or trans isomers. In the unfolded state of proteins, the peptide groups are free to isomerize and adopt