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DAR is found in 76 entries

DAR in polymers: 71 entries. Examples include: 5KWO 1CW8 2KQL

DAR as free ligands, exist in 5 entries. Example includes: 3KO9 4GVZ 4M2C

Find related ligands: Stereoisomers Similar ligands Chemical Structure Search

View summary at Ligand Expo

Chemical Component Summary

FormulaC6 H15 N4 O2
Molecular Weight175.21 g/mol
Isomeric SMILESN[C@H](CCCNC(N)=[NH2+])C(O)=O

Chemical Details

Formal Charge1
Atom Count27
Chiral Atom Count1
Chiral AtomsCA
Bond Count26
Aromatic Bond Count0
Leaving Atomsn/a

Drug Info: DrugBank

DrugBank IDDB00125 Different stereochemistry
  • approved
  • nutraceutical
DescriptionAn essential amino acid that is physiologically active in the L-form.
  • (2S)-2-amino-5-(carbamimidamido)pentanoic acid
  • (2S)-2-amino-5-guanidinopentanoic acid
  • (S)-2-amino-5-guanidinopentanoic acid
  • (S)-2-Amino-5-guanidinovaleric acid
  • Arg
SaltsL-Arginine Hydrochloride
Brand Names
  • Aminosyn
  • Aminosyn 10%
  • Aminosyn 10% W Electrolytes
  • Aminosyn 3.5% M
  • Aminosyn 5%
Affected OrganismHumans and other mammals
IndicationUsed for nutritional supplementation, also for treating dietary shortage or imbalance.
PharmacologyStudies have shown that is has improved immune responses to bacteria, viruses and tumor cells; promotes wound healing and regeneration of the liver; causes the release of growth hormones; considered crucial for optimal muscle growth and tissue repair.
Mechanism of actionMany of supplemental L-arginine's activities, including its possible anti-atherogenic actions, may be accounted for by its role as the precursor to nitric oxide or NO. NO is produced by all tissues of the body and plays very important roles in the cardiovascular system, immune system and nervous system. NO is formed from L-arginine via the enzyme nitric oxide synthase or synthetase (NOS), and the effects of NO are mainly mediated by 3,'5' -cyclic guanylate or cyclic GMP. NO activates the enzyme guanylate cyclase, which catalyzes the synthesis of cyclic GMP from guanosine triphosphate or GTP. Cyclic GMP is converted to guanylic acid via the enzyme cyclic GMP phosphodiesterase. NOS is a heme-containing enzyme with some sequences similar to cytochrome P-450 reductase. Several isoforms of NOS exist, two of which are constitutive and one of which is inducible by immunological stimuli. The constitutive NOS found in the vascular endothelium is designated eNOS and that present in the brain, spinal cord and peripheral nervous system is designated nNOS. The form of NOS induced by immunological or inflammatory stimuli is known as iNOS. iNOS may be expressed constitutively in select tissues such as lung epithelium. All the nitric oxide synthases use NADPH (reduced nicotinamide adenine dinucleotide phosphate) and oxygen (O2) as cosubstrates, as well as the cofactors FAD (flavin adenine dinucleotide), FMN (flavin mononucleotide), tetrahydrobiopterin and heme. Interestingly, ascorbic acid appears to enhance NOS activity by increasing intracellular tetrahydrobiopterin. eNOS and nNOS synthesize NO in response to an increased concentration of calcium ions or in some cases in response to calcium-independent stimuli, such as shear stress. In vitro studies of NOS indicate that the Km of the enzyme for L-arginine is in the micromolar range. The concentration of L-arginine in endothelial cells, as well as in other cells, and in plasma is in the millimolar range. What this means is that, under physiological conditions, NOS is saturated with its L-arginine substrate. In other words, L-arginine would not be expected to be rate-limiting for the enzyme, and it would not appear that supraphysiological levels of L-arginine which could occur with oral supplementation of the amino acid^would make any difference with regard to NO production. The reaction would appear to have reached its maximum level. However, in vivo studies have demonstrated that, under certain conditions, e.g. hypercholesterolemia, supplemental L-arginine could enhance endothelial-dependent vasodilation and NO production.
Route of administration
  • Intravenous
  • Amino Acids
  • Amino Acids, Basic
  • Amino Acids, Diamino
  • Amino Acids, Essential
  • Amino Acids, Peptides, and Proteins
CAS number74-79-3
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS. Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID:21059682