MeSH

from dinoflagellate Gymnodinium breve

Date introduced: December 19, 1984

Natural compounds containing alternating carbonyl and methylene groups (beta-polyketones), bioenergenetically derived from repeated condensation of acetyl coenzyme A via malonyl coenzyme A, in a process similar to fatty acid synthesis.

Year introduced: 2012

Cyclic compounds with a ring size of approximately 1-4 dozen atoms.

Year introduced: 2005

Compounds based on an 8-membered heterocyclic ring including an oxygen. They can be considered medium ring ethers.

Year introduced: 2003

Specific, characterizable, poisonous chemicals, often PROTEINS, with specific biological properties, including immunogenicity, produced by microbes, higher plants (PLANTS, TOXIC), or ANIMALS.

Year introduced: 2006(1966)

Compounds which contain two or more rings in their structure.

Year introduced: 2005(1974)

A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.

Year introduced: 1998

Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous FISHES.

Year introduced: 1974

Cyclic esters of hydroxy carboxylic acids, containing a 1-oxacycloalkan-2-one structure. Large cyclic lactones of over a dozen atoms are MACROLIDES.

Organic compounds that contain a ring structure made up of carbon and one or more additional elements such as nitrogen and oxygen.

Year introduced: 1998

Cyclic compounds that include atoms other than carbon in their ring structure.

Compounds of the general formula R-O-R arranged in a ring or crown formation.

Organic compounds having two alkyl or aryl groups bonded to an oxygen atom, as in the formula R1–O–R2.

Endogenously synthesized compounds that influence biological processes not otherwise classified under ENZYMES; HORMONES or HORMONE ANTAGONISTS.

Year introduced: 1989

Polycyclic polyether polyketides most often produced by marine organisms, e.g., DINOFLAGELLATES. Many polyether marine toxins are ionophores and neurotoxins and responsible for seafood poisoning.

Year introduced: 2024

Polycyclic polyketides with distinctive ladder shaped multiple polyether motifs. In STREPTOMYCES polycyclic polyketide backbones are assembled by type I modular polyketide synthases which then are modified by epoxidase and epoxide hydrolase to achieve their stereochemistry. Polyether ionophore antibiotics coordinate alkali metal cations with their multiple oxygen atoms which disturbs sodium/potassium concentration gradient. They are widely used to treat and control COCCIDIOSIS. Structurally related MARINE LADDER POLYETHERS are neurotoxins.

Year introduced: 2024