Cyclic hemiacetals formed by intramolecular addition of a hydroxy group to an aldehydic or ketonic carbonyl group. They are thus 1-oxacycloalkan-2-ols or unsaturated analogues.
| Member | Definition | Role |
|---|
| 2-hydroxy-1,4-benzoxazin-3-one | A benzoxazine bearing hydroxy and oxo substituents at positions 2 and 3 respectively. | HBOA |
| 2,4-dihydroxy-1,4-benzoxazin-3-one | A lactol that consists of 1,4-benzoxazine bearing two hydroxy substituents at positions 2 and 4 as well as a keto group at position 3. | DIBOA |
| 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one | A lactol that is DIBOA in which the hydrogen at position 7 is replaced by a methoxy group. It has been isolated from the maize plants. | DIMBOA |
| 2,7,4'-trihydroxyisoflavanone | A hydroxyisoflavanone that is isoflavanone with hydroxy substituents at positions 2, 7 and 4'. | 2,4',7-trihydroxyisoflavanone |
| capilliposide b | A triterpenoid saponin that consists of anagalligenin A substituted by a caproyl group at position 22 and a beta-D-xylopyranosyl-(1->2)-beta-D-glucopyranosyl-(1->4)-[beta-D-glucopyranosyl-(1->2)]-alpha-L-arabinopyranosyl moiety at position 3 via a glycosidic linkage. It is isolated from the whole plants of Lysimachia capillipes and has been shown to exhibit potent cytotoxicity against human A-2780 cells. | capilliposide B |
| cubebin | A lignan that consists of tetrahydrofuran-2-ol substituted by two 1,3-benzodioxol-5-ylmethyl groups at positions 3 and 4 respectively (the 2S,3R,4R stereoisomer). It is isolated from the leaves of Piper nigrum and exhibits analgesic, anti-inflammatory, antimicrobial and trypanocidal activities. | (-)-cubebin |
| elaiophylin | A macrodiolide that is isolated from several bacteria including Streptomyces violaceoniger and other soil actinomycetes. | elaiophylin |
| enfumafungin | A triterpene glycoside and hemiacetal isolated from a fermentation of Hormonema sp. and which specifically inhibits glucan synthesis in fungal cells. | enfumafungin |
| komaroviquinone | A tetracyclic diterpenoid isolated from Dracocephalum komarovii and has been shown to exhibit trypanocidal activity. | komaroviquinone |
| l 683590 | A macrolide that is produced by the fermentation of Streptomyces hygroscopicus and exhibits strong immunosuppressant properties. | ascomycin |
| manoalide | A sesterterpenoid isolated from the marine sponge Luffariella variabilis and which has been shown to exhibit inhibitory activity towards phospholipase A2. | manoalide |
| myriaporone 3 | A member of the class of oxanes isolated from the Mediterranean bryozoan Myriapora truncata and has been shown to exhibit inhibitory activity against murine leukemia cells. | myriaporone 3 |
| nepetalactol | A cyclopentapyran that is 1,4a,5,6,7,7a-hexahydrocyclopenta[c]pyran substituted at position 1 by a hydroxy group and at positions 4 and 7 by methyl groups (the 4aS,7S,7aR-diastereomer) | cis-trans-nepetalactol |
| oleuropein aglycone | A secoiridoid that is the methyl ester of 3,4-dihydro-2H-pyran-5-carboxylic acid which is substituted at positions 2, 3, and 4 by hydroxy, ethylidene, and carboxymethyl groups, respectively and in which the carboxylic acid moiety of the carboxymethyl substituent has been converted to the corresponding 3,4-dihydroxyphenethyl ester (the 2R,3E,4S stereoisomer). The most important phenolic compound present in olive cultivars. | oleuropein aglycone |
| oxypaeoniflora | A monoterpene glycoside with formula C23H28O12, isolated from several species of Paeoniae. | oxypaeoniflorin |
| paeoniflorigenone | A terpenoid with formula C17H18O6, isolated from several species of Paeoniae. | paeoniflorigenone |
| patulin | A furopyran and lactone that is (2H-pyran-3(6H)-ylidene)acetic acid which is substituted by hydroxy groups at positions 2 and 4 and in which the hydroxy group at position 4 has condensed with the carboxy group to give the corresponding bicyclic lactone. A mycotoxin produced by several species of Aspergillus and Penicillium, it has antibiotic properties but has been shown to be carcinogenic and mutagenic. | patulin |
| versiconal | An anthrafuran that is 2,3-dihydroanthra[2,3-b]furan-5,10-dione substituted at positions 2, 4, 6 and 8 by hydroxy groups and at position 3 by a 2-hydroxyethyl group. An intermediate in the biosynthesis of aflatoxin. | versiconal hemiacetal |
| versiconal hemiacetal acetate | An anthrafuran that is 2,3-dihydroanthra[2,3-b]furan-5,10-dione substituted at positions 2, 4, 6 and 8 by hydroxy groups and at position 3 by a 2-acetoxyethyl group. An intermediate in the biosynthesis of aflatoxin. | versiconal hemiacetal acetate |