SynCED: Okadaic acid

Record Information

Version

1.0

Creation Date

2014-08-29 04:49:29 UTC

Update Date

2026-05-14 17:30:01 UTC

Accession Number

CHEM002989

Identification

Common Name

Okadaic acid

Class

Small Molecule

Description

Okadaic acid is found in mollusks. Okadaic acid is found in the marine sponges Halichondria okadai and Halichondria melanodocia and shellfish. It is a metabolite of Prorocentrum lima. It is a diarrhetic shellfish toxin. Okadaic acid is a toxin that accumulates in bivalves and causes diarrhetic shellfish poisoning. The molecular formula of okadaic acid, which is a derivative of a C38 fatty acid, is C44H68O13. The IUPAC name of okadaic acid is (2R)-2-hydroxy-3-{(2S,5R,6R,8S)-5-hydroxy-[(1R,2E)-3-((2R,5R,6'S,8'R,8a'S)-8'-hydroxy-6'-{(1S,3S)-1-hydroxy-3-[(3R,6S)-3-methyl-1,7-dioxaspiro[5.5]undec-2-yl]butyl}-7'-methyleneoctahydro-3H,3'H-spiro[furan-2,2'-pyrano[3,2-b]pyran]-5-yl)-1-methylprop-2-en-1-yl]-10-methyl-1,7-dioxaspiro[5.5]undec-10-en-2-yl}-2-methylpropanoic acid. Okadaic acid was named from the marine sponge Halichondria okadai, from which okadaic acid was isolated for the first time. It has also been isolated from another marine sponge, H. malanodocia, as a cytotoxin. The real producer of okadaic acid is a marine dinoflagellate. Okadaic acid has been shown to exhibit anti-tumor, signalling, apoptotic and lipolytic functions Okadaic acid belongs to the family of Okadaic Acids and Derivatives. These are heat-stable polyether and lipophilic compounds that accumulate in the fatty tissue of shellfish. (1, 2, 3, 4).

Contaminant Sources

FooDB Chemicals
STOFF IDENT Compounds
T3DB toxins

Contaminant Type

Animal Toxin
Ether
Food Toxin
Human Neurotoxin
Ionophore
Marine Toxin
Metabolite
Natural Compound
Organic Compound
PFAS

Chemical Structure

MOL SDF PDB SMILES InChI

Synonyms

Value	Source
Okadaate	Generator
9,10-Deepithio-9,10-didehydroacanthifolicin	HMDB
PL Toxin II	HMDB
2-Hydroxy-3-{5-hydroxy-8-[(3E)-4-[8'-hydroxy-6'-(1-hydroxy-3-{3-methyl-1,7-dioxaspiro[5.5]undecan-2-yl}butyl)-7'-methylidene-hexahydro-3'H-spiro[oxolane-2,2'-pyrano[3,2-b]pyran]-5-yl]but-3-en-2-yl]-10-methyl-1,7-dioxaspiro[5.5]undec-10-en-2-yl}-2-methylpropanoate	HMDB
Acid, ocadaic	HMDB
Acid, okadaic	HMDB
Ocadaic acid	HMDB
Okadaic acid	MeSH

Chemical Formula

C₄₄H₆₈O₁₃

Average Molecular Mass

805.003 g/mol

Monoisotopic Mass

804.466 g/mol

CAS Registry Number

78111-17-8

IUPAC Name

2-hydroxy-3-{5-hydroxy-8-[(3E)-4-[8'-hydroxy-6'-(1-hydroxy-3-{3-methyl-1,7-dioxaspiro[5.5]undecan-2-yl}butyl)-7'-methylidene-hexahydro-3'H-spiro[oxolane-2,2'-pyrano[3,2-b]pyran]-5-yl]but-3-en-2-yl]-10-methyl-1,7-dioxaspiro[5.5]undec-10-en-2-yl}-2-methylpropanoic acid

Traditional Name

2-hydroxy-3-{5-hydroxy-8-[(3E)-4-[8'-hydroxy-6'-(1-hydroxy-3-{3-methyl-1,7-dioxaspiro[5.5]undecan-2-yl}butyl)-7'-methylidene-hexahydrospiro[oxolane-2,2'-pyrano[3,2-b]pyran]-5-yl]but-3-en-2-yl]-10-methyl-1,7-dioxaspiro[5.5]undec-10-en-2-yl}-2-methylpropanoic acid

SMILES

CC(CC(O)C1OC2CCC3(CCC(O3)\C=C\C(C)C3CC(C)=CC4(OC(CC(C)(O)C(O)=O)CCC4O)O3)OC2C(O)C1=C)C1OC2(CCCCO2)CCC1C

InChI Identifier

InChI=1S/C44H68O13/c1-25-21-34(55-44(23-25)35(46)12-11-31(54-44)24-41(6,50)40(48)49)26(2)9-10-30-14-18-43(53-30)19-15-33-39(57-43)36(47)29(5)38(52-33)32(45)22-28(4)37-27(3)13-17-42(56-37)16-7-8-20-51-42/h9-10,23,26-28,30-39,45-47,50H,5,7-8,11-22,24H2,1-4,6H3,(H,48,49)/b10-9+

InChI Key

QNDVLZJODHBUFM-MDZDMXLPSA-N

Chemical Taxonomy

Description

Belongs to the class of organic compounds known as ketals. These are acetals derived from ketones by replacement of the oxo group by two hydrocarbyloxy groups R2C(OR)2 ( R not Hydrogen ). This term, once abandoned, has been reinstated as a subclass of acetals.

Kingdom

Organic compounds

Super Class

Organic oxygen compounds

Class

Organooxygen compounds

Sub Class

Ethers

Direct Parent

Ketals

Alternative Parents

Substituents

Ketal
Alpha-hydroxy acid
Hydroxy acid
Oxane
Pyran
Tertiary alcohol
Tetrahydrofuran
Secondary alcohol
Organoheterocyclic compound
Oxacycle
Monocarboxylic acid or derivatives
Dialkyl ether
Carboxylic acid
Carboxylic acid derivative
Hydrocarbon derivative
Carbonyl group
Organic oxide
Alcohol
Aliphatic heteropolycyclic compound

Molecular Framework

Aliphatic heteropolycyclic compounds

External Descriptors

Not Available

Biological Properties

Status

Detected and Not Quantified

Origin

Exogenous

Cellular Locations

Membrane

Biofluid Locations

Not Available

Tissue Locations

Not Available

Pathways

Not Available

Applications

Not Available

Biological Roles

Chemical Roles

EC 3.1.3.16 (phosphoprotein phosphatase) inhibitor

Physical Properties

State

Solid

Appearance

White powder.

Experimental Properties

Property	Value
Melting Point	164 - 166°C
Boiling Point	Not Available
Solubility	Not Available

Predicted Properties

Property	Value	Source
Water Solubility	0.0044 g/L	ALOGPS
logP	2.73	ALOGPS
logP	5.13	ChemAxon
logS	-5.3	ALOGPS
pKa (Strongest Acidic)	3.76	ChemAxon
pKa (Strongest Basic)	-3.2	ChemAxon
Physiological Charge	-1	ChemAxon
Hydrogen Acceptor Count	13	ChemAxon
Hydrogen Donor Count	5	ChemAxon
Polar Surface Area	182.83 Å²	ChemAxon
Rotatable Bond Count	10	ChemAxon
Refractivity	210.78 m³·mol⁻¹	ChemAxon
Polarizability	88.49 Å³	ChemAxon
Number of Rings	7	ChemAxon
Bioavailability	No	ChemAxon
Rule of Five	No	ChemAxon
Ghose Filter	No	ChemAxon
Veber's Rule	No	ChemAxon
MDDR-like Rule	Yes	ChemAxon

Spectra

Toxicity Profile

Route of Exposure

Not Available

Mechanism of Toxicity

Okadaic acid (OA) dramatically increases both nerve growth factor (NGF) mRNA content (50-fold) and NGF secretion (100-fold) in astrocytes. Okadaic acid also activated NGF gene transcription, which was preceded by an induction of c-fos and c-jun gene transcription. The induction of NGF expression by okadaic acid appeared independent from protein kinase C activity because down-regulating protein kinase C activity failed to decrease the okadaic acid stimulation. Results indicate that okadaic acid profoundly stimulates NGF expression in astrocytes mainly by enhancing NGF mRNA stability and suggest important roles for phosphoprotein phosphatases in regulating NGF production. Instead of activating protein kinase C like the phorbol ester tumor promoters, OA specifically inhibits phosphoprotein phosphatases 1 and 2A leading to an increase in the phosphorylation state of many cellular proteins. Interestingly, OA treatment of fibroblasts mimicked the effects of IL-1 on protein phosphorylation, suggesting that one cellular action of IL-1 might be to inhibit phosphoprotein phosphatase activity. OA has also been found to increase NGF mRNA content in mixed glial-neuronal hippocampal cell cultures similar to IL-1. The toxic potency of this phycotoxin is highly associated with the presence of the free carboxylic acid. Therefore, the toxin forms where the carboxylic acid is acylated are less toxic. However, it is clear that enzymatic hydrolisis after consumption of contaminated shellfish can occur, therefore liberating the free acid. (PMID: 19925818; PMID: 7890729)

Metabolism

Not Available

Toxicity Values

Not Available

Lethal Dose

Not Available

Carcinogenicity (IARC Classification)

No indication of carcinogenicity to humans (not listed by IARC).

Uses/Sources

Okadaic acid is found in mollusks. Okadaic acid is found in the marine sponges Halichondria okadai and Halichondria melanodocia and shellfish. It is a diarrhetic shellfish toxin. Okadaic acid is a toxin that accumulates in bivalves and causes diarrhetic shellfish poisoning. Okadaic acid was named from the marine sponge Halichondria okadai, from which okadaic acid was isolated for the first time. It has also been isolated from another marine sponge, H. malanodocia, as a cytotoxin.

Minimum Risk Level

Not Available

Health Effects

Not Available

Symptoms

Not Available

Treatment

Not Available

Concentrations

Not Available

External Links

DrugBank ID