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Record Information
StatusDetected and Quantified
Creation Date2019-02-15 22:30:46 UTC
Update Date2020-05-28 21:15:52 UTC
Secondary Accession NumbersNone
Metabolite Identification
Common NameSuccinylaminoimidazole carboxamide riboside
DescriptionSuccinylaminoimidazole carboxamide riboside, also known as SAICAr, is the riboside form of the better known compound SAICAR (the ribotide). Ribosides chemically resemble ribotides except they do not contain a phosphate group. The appearance of succinylaminoimidazolecarboxamide riboside (SAICAriboside) and succinyladenosine (S-Ado) in cerebrospinal fluid, in urine, and, to a lesser extent, in plasma is characteristic of a heritable deficiency known as adenylosuccinate lyase deficiency (ADSL). Adenylosuccinate lyase deficiency is responsible for a range of symptoms that involve psychomotor retardation, often accompanied by epileptic seizures, and autistic features. In adenylosuccinate lyase deficiency it is believed that the buildup of SAICAr causes neurotoxic effects. In the severely affected individuals, the concentration levels of SAICAr and S-Ado are comparable, whereas in people with milder forms of the disease, the concentration of S-Ado is more than double that of those more severely affected, while SAICAr concentration levels remain comparable. Therefore, when present in sufficiently high levels, SAICAr can act as a metabotoxin and an acidogen. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of untreated adenylosuccinate lyase deficiency. Many affected children with organic acidemias experience intellectual disability or delayed development.
SAICA ribosideHMDB
(2S)-2-[5-Amino-1-(beta-D-ribosyl)imidazole-4-carboxamido]succinic acidHMDB
Succinylaminoimidazolecarboxamide riboseHMDB
(2S)-2-[5-Amino-1-(b-D-ribosyl)imidazole-4-carboxamido]succinic acidHMDB
(2S)-2-[5-Amino-1-(β-D-ribosyl)imidazole-4-carboxamido]succinic acidHMDB
(S)-2-[5-Amino-1-(D-ribosyl)imidazole-4-carboxamido]succinic acidHMDB
Succinylaminoimidazole carboxamide ribosideHMDB
Chemical FormulaC13H18N4O9
Average Molecular Weight374.306
Monoisotopic Molecular Weight374.107378176
IUPAC Name(2S)-2-({5-amino-1-[(2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]-1H-imidazol-4-yl}formamido)butanedioic acid
Traditional Name(2S)-2-({5-amino-1-[(2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]imidazol-4-yl}formamido)butanedioic acid
CAS Registry Number17388-80-6
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as 1-ribosyl-imidazolecarboxamides. These are organic compounds containing the imidazole ring linked to a ribose ring through a 1-2 bond.
KingdomOrganic compounds
Super ClassNucleosides, nucleotides, and analogues
ClassImidazole ribonucleosides and ribonucleotides
Sub Class1-ribosyl-imidazolecarboxamides
Direct Parent1-ribosyl-imidazolecarboxamides
Alternative Parents
  • 1-ribosyl-imidazolecarboxamide
  • Aspartic acid or derivatives
  • N-acyl-alpha amino acid or derivatives
  • N-acyl-alpha-amino acid
  • N-glycosyl compound
  • Glycosyl compound
  • Pentose monosaccharide
  • Alpha-amino acid or derivatives
  • 2-heteroaryl carboxamide
  • Imidazolyl carboxylic acid derivative
  • Imidazole-4-carbonyl group
  • N-substituted imidazole
  • Monosaccharide
  • Aminoimidazole
  • Dicarboxylic acid or derivatives
  • Imidazole
  • Vinylogous amide
  • Tetrahydrofuran
  • Azole
  • Heteroaromatic compound
  • Amino acid or derivatives
  • Amino acid
  • Carboxamide group
  • Secondary carboxylic acid amide
  • Secondary alcohol
  • Carboxylic acid derivative
  • Organoheterocyclic compound
  • Azacycle
  • Oxacycle
  • Carboxylic acid
  • Organonitrogen compound
  • Hydrocarbon derivative
  • Amine
  • Organic oxygen compound
  • Alcohol
  • Carbonyl group
  • Organic oxide
  • Organopnictogen compound
  • Organic nitrogen compound
  • Primary amine
  • Primary alcohol
  • Organooxygen compound
  • Aromatic heteromonocyclic compound
Molecular FrameworkAromatic heteromonocyclic compounds
External DescriptorsNot Available
Not Available
Physical Properties
StateNot Available
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
pKa (Strongest Acidic)2.99ChemAxon
pKa (Strongest Basic)4.55ChemAxon
Physiological Charge-2ChemAxon
Hydrogen Acceptor Count11ChemAxon
Hydrogen Donor Count7ChemAxon
Polar Surface Area217.46 ŲChemAxon
Rotatable Bond Count7ChemAxon
Refractivity79.78 m³·mol⁻¹ChemAxon
Polarizability34.04 ųChemAxon
Number of Rings2ChemAxon
Rule of FiveNoChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Not Available
Biological Properties
Cellular LocationsNot Available
Biospecimen Locations
  • Urine
Tissue LocationsNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
UrineDetected and Quantified214 umol/mmol creatinineAdult (>18 years old)BothAdenylosuccinate lyase deficiency details
Associated Disorders and Diseases
Disease References
Adenylosuccinate lyase deficiency
  1. Wevers RA, Engelke UF, Moolenaar SH, Brautigam C, de Jong JG, Duran R, de Abreu RA, van Gennip AH: 1H-NMR spectroscopy of body fluids: inborn errors of purine and pyrimidine metabolism. Clin Chem. 1999 Apr;45(4):539-48. [PubMed:10102915 ]
Associated OMIM IDs
  • 103050 (Adenylosuccinate lyase deficiency)
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDNot Available
KNApSAcK IDNot Available
Chemspider IDNot Available
KEGG Compound IDNot Available
BioCyc IDNot Available
BiGG IDNot Available
Wikipedia LinkNot Available
METLIN IDNot Available
PubChem Compound54478644
PDB IDNot Available
ChEBI IDNot Available
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB ID
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Keller KE, Tan IS, Lee YS: SAICAR stimulates pyruvate kinase isoform M2 and promotes cancer cell survival in glucose-limited conditions. Science. 2012 Nov 23;338(6110):1069-72. doi: 10.1126/science.1224409. Epub 2012 Oct 18. [PubMed:23086999 ]