Any of the naturally occurring, basic nitrogen compounds (mostly heterocyclic) occurring mostly in the plant kingdom, but also found in bacteria, fungi, and animals. By extension, certain neutral compounds biogenetically related to basic alkaloids are also classed as alkaloids. Amino acids, peptides, proteins, nucleotides, nucleic acids, amino sugars and antibiotics are not normally regarded as alkaloids. Compounds in which the nitrogen is exocyclic (dopamine, mescaline, serotonin, etc.) are usually classed as amines rather than alkaloids.
| Member | Definition | Role |
|---|
| 1-O-Acetyllycorine | | 1-O-Acetyllycorine |
| 11-bromovincamine | | brovincamine |
| 16-epivincamine | | 16-epivincamine |
| 18-Hydroxy-11,17-dimethoxyyohimban-16-carboxylic acid | | 18-Hydroxy-11,17-dimethoxyyohimban-16-carboxylic acid |
| 3-(4-methoxyphenyl)-3-[[2-(4-methoxyphenyl)-1-oxoethyl]amino]propanoic acid | | 3-(4-methoxyphenyl)-3-[[2-(4-methoxyphenyl)-1-oxoethyl]amino]propanoic acid |
| 5-methoxycanthin-6-one | | 5-Methoxycanthin-6-one |
| 5,6-dihydro-9-hydroxy-10-methoxybenzo(g)-1,3-benzodioxolo(5,6-a)quinolizinium chloride | | Berberrubine |
| 5,7-dihydroxy-2-methyl-8-(4-(3-hydroxy-1-methyl)-piperidinyl)-4h-1-benzopyran-4-one | A member of the class of chromones that is 4H-chromen-4-one in which the hydrogens at positions 2,5,7 and 8 are replaced by methyl, hydroxy, hydroxy, and (3S,4R)-3-hydroxy-1-methylpiperidin-4-yl groups, respectively. It is an alkaloid initially isolated from Amoora rohituka and is a precursor of the anti-cancer compound flavopiridol. | rohitukine |
| 7-hydroxymitragynine | | 7-Hydroxymitragynine |
| 8-hydroxymanzamine a | An alkaloid that is manzamine A with a hydroxy substituent at position 8. Isolated from Pachypellina and Acanthostrongylophora, it exhibits inhibitory activity against Glycogen Synthase Kinase-3 (EC 2.7.11.26). | 8-hydroxymanzamine A |
| acronine | An alkaloid antineoplastic agent isolated from Acronychia baueri. | acronycine |
| acutumine | | Acutumine |
| ageladine a | An imidazopyridine that is 1H-imidazo[4,5-c]pyridin-2-amine substituted by a 4,5-dibromo-1H-pyrrol-2-yl group at position 4. It is an alkaloid isolated from a marine sponge Agelas nakamurai and acts as an inhibitor of the matrix metalloproteinases, the key enzymes involved in tumour growth, migration, angiogenesis, invasion and metastasis. | ageladine A |
| Amalorin | | Amalorin |
| anagyrine | | Anagyrine |
| annomontine | An alkaloid that is beta-carboline substituted at position C-1 by a 2-aminopyrimidin-4-yl moiety. An antiparasitic agent found in Annona montana and Annona foteida. | annomontine |
| antofine | An organic heteropentacyclic compound that is (13aR)-9,11,12,13,13a,14-hexahydrodibenzo[f,h]pyrrolo[1,2-b]isoquinoline substituted at positions 2, 3 and 6 by methoxy groups. It is an alkaloid produced by relatives of the milkweed family and exhibits antiviral, anti-inflammatory, antiadipogenic and antitumorigenic activities. | (-)-antofine |
| asperparaline a | An alkaloid isolated from Aspergillus aculeatus. | asperparaline A |
| atherospermine | | Atherosperminine |
| batzelladine a | A carboxylic ester obtained by the formal condensation of (2aS,3S,4R,7R,8aS)-4-methyl-7-nonyl-2,2a,3,4,6,7,8,8a-octahydro-1H-5,6,8b-triazaacenaphthylene-3-carboxylic acid with the hydroxy group of 4-carbamimidamidobutyl (3R)-3-(9-hydroxynonyl)-1-imino-1,2,3,5,6,7-hexahydropyrrolo[1,2-c]pyrimidine-4-carboxylate. Isolated from a bright red Caribbean sponge, Batzella, it has potential anti-HIV activity. | batzelladine A |
| caracurine v | | Caracurine V |
| carpaine | An alkaloid that forms a major component of the papaya leaves and has been shown to exhibit cardiovascular effects. | carpaine |
| ceratamine a | An organic heterobicyclic compound, which is imidazo[4,5-d]azepin-5(6H)-one substituted by a 3,5-dibromo-4-methoxybenzyl group at position 4, a methyl group at position 6 and a methylamino group at position 2. It is an antimitotic alkaloid isolated from the marine sponge Pseudoceratina. | ceratamine A |
| colchicine | A colchicine that has (S)-configuration. It is a secondary metabolite, has anti-inflammatory properties and is used to treat gout, crystal-induced joint inflammation, familial Mediterranean fever, and many other conditions. | (S)-colchicine |
| colchicine, (+-)-isomer | An alkaloid that is a carbotricyclic compound comprising 5,6,7,9-tetrahydrobenzo[a]heptalene having four methoxy substituents at the 1-, 2-, 3- and 10-positions as well as an oxo group at the 9-position and an acetamido group at the 7-position. It has been isolated from the plants belonging to genus Colchicum. | colchicine |
| coptisine | | coptisine |
| crambescidin 800 | An organic heteropentacyclic guanidine alkaloid isolated from the marine sponge Crambe crambe and Batzella. It exhibits anti-HIV-1 and anti-HSV-1 activity. | crambescidin 800 |
| crinine | | Crinine |
| croomine | | croomine |
| cryptopleurine | An organic heteropentacyclic compound that is (14aR)-11,12,13,14,14a,15-hexahydro-9H-dibenzo[f,h]pyrido[1,2-b]isoquinoline substituted at positions 2, 3 and 6 by methoxy groups. | cryptopleurine |
| cularine | | Cularine |
| cytisine | An organic heterotricyclic compound that is the toxic principle in Laburnum seeds and is found in many members of the Fabaceae (legume, pea or bean) family. An acetylcholine agonist, it is widely used throughout Eastern Europe as an aid to giving up smoking. | cytisine |
| decarbamylsaxitoxin | A pyrrolopurine that is 2,6-diiminodecahydropyrrolo[1,2-c]purine carrying an additional hydroxymethyl substituent at position 4 as well as two hydroxy substituents at position 10. A toxin that is isolated from marine dinoflagellates and cyanobacteria and is known to cause paralytic shellfish poisoning. | decarbamoylsaxitoxin |
| dehydrocorydalin | | Dehydrocorydaline |
| demecolcine | A secondary amino compound that is (S)-colchicine in which the N-acetyl group is replaced by an N-methyl group. Isolable from the autumn crocus, Colchicum autumnale, it is less toxic than colchicine and is used as an antineoplastic. | (-)-demecolcine |
| demissidine | | Demissidine |
| dibromophakellin | An alkaloid isolated from the marine sponge Phakellia flabellata and Acanthella costata. It acts as an alpha2B adrenoceptor agonist. | (-)-dibromophakellin |
| dihydroberberine | | Lambertine |
| dimethoxyphenylethylamine | An aromatic ether that is the derivative of 2-phenylethylamine with methoxy substituents at the 3- and 4-positions. It is an alkaloid isolated from the Cactaceae family. | 3,4-dimethoxyphenylethylamine |
| discretamine | | (R,S)-Scoulerine |
| eburnamonine | | Eburnamenin-14(15H)-one |
| elymoclavine | | Elymoclavine |
| epibatidine | | 3-(6-chloro-3-pyridinyl)-7-azabicyclo[2.2.1]heptane |
| erythraline | | (+)-Erythraline |
| galantamine | | LSM-1597 |
| gamma-lumicolchicine | | LSM-4236 |
| hamayne | | Hamayne |
| Harringtonine | | Harringtonine |
| hemanthamine | | Haemanthamine |
| hirsutine, (16e,20beta)-isomer | | Corynantheidine |
| jatrorrhizine | | Jatrorrhizine |
| leuconoxine | | leuconoxine |
| LSM-16753 | | LSM-16753 |
| LSM-22634 | | LSM-22634 |
| LSM-24185 | | LSM-24185 |
| lycojapodine a | An alkaloid isolated from the club moss Lycopodium japonicum and has been shown to exhibit acetylcholinesterase inhibitory and anti-HIV-1 activity. | lycojapodine A |
| lycorenine | | Lycorenine |
| manzamine a | An alkaloid of the class of beta-carbolines isolated from Haliclona and Acanthostrongylophora. It exhibits inhibitory activity against Glycogen Synthase Kinase-3 (EC 2.7.11.26). | manzamine A |
| massadine | An alkaloid isolated from Stylissa massa. | massadine |
| matrine | | Matrine |
| muromonab-cd3 | An organic heteropentacyclic compound that is isolated from the marine sponge Xestospongia exigua. | xestospongin C |
| muscimol | A member of the class of isoxazoles that is 1,2-oxazol-3(2H)-one substituted by an aminomethyl group at position 5. It has been isolated from mushrooms of the genus Amanita. | muscimol |
| n-methylphenylethanolamine | An alkaloid that is ethanolamine having the phenyl group at the 1-position and a methyl group attached to the nitrogen. It has been isolated from Halostachys caspica. | N-methylphenylethanolamine |
| neotuberostemonine | | neotuberostemonine |
| norcoralydine | | Xylopinine |
| nostocarboline | A member of the class of beta-carbolines that is 9H-beta-carbolin-2-ium substituted by a chloro group at position 6 and a methyl group at position 2. It is isolated from a fresh water cyanobacterium Nostoc 78-12A and acts as an inhibitor of butyrylcholinesterase. | nostocarboline |
| oxymatrine | | Ammothamnine |
| peiminine | | Imperialine |
| phenethylamine | A phenylethylamine having the phenyl substituent at the 2-position. | 2-phenylethylamine |
| pipercallosidine | An enamide that is (2E)-N-isobutylhept-2-enamide which is substituted at position 7 by a 3,4-methylenedioxyphenyl group. A natural product found in Piper sarmentosum. | pipercallosidine |
| piperlactam s | An organic heterotetracyclic compound that is dibenzo[cd,f]indol-4(5H)-one carrying two methoxy substituents at positions 1 and 5 as well as a hydroxy substituent at position 2. | piperlactam S |
| piperolactam a | | Piperolactam A |
| pretazettine | | Pretazettine |
| protoverine | | Protoverine |
| pumiliotoxin a | | Pumiliotoxin A |
| pyrrolnitrin | A member of the class of pyrroles carrying chloro and 3-chloro-2-nitrophenyl substituents at positions 3 and 4 respectively. | pyrrolnitrin |
| quebrachamine | | (-)-Quebrachamine |
| sampangine | A copyrine alkaloid with formula C15H8N2O, extracted from several plants including the stem bark of Cananga odorata. It is a heme biosynthesis inhibitor and exhibits antifungal and anticancer properties. | sampangine |
| saxitoxin | An alkaloid isolated from the marine dinoflagellates and cyanobacteria that causes paralytic shellfish poisoning. | saxitoxin |
| stachydrine | An amino acid betaine that is L-proline zwitterion in which both of the hydrogens attached to the nitrogen are replaced by methyl groups. | L-proline betaine |
| tetramethylpyrazine | A member of the class of pyrazines that is pyrazine in which all four hydrogens have been replaced by methyl groups. An alkaloid extracted from Chuanxiong (Ligusticum wallichii). | tetramethylpyrazine |
| toxiferine | | Toxiferine I |
| trigonelline | An iminium betaine that is the conjugate base of N-methylnicotinic acid, arising from deprotonation of the carboxy group. | N-methylnicotinate |
| trimethylcolchicinic acid methyl ether | | Deacetylcolchicine |
| tuberostemonine | | tuberostemonine |
| u-47929 | | ficellomycin |
| undecylprodigiosin | A member of the class of tripyrroles that is 1H-pyrrole substituted by (4'-methoxy-1H,5'H-[2,2'-bipyrrol]-5'-ylidene)methyl and undecyl groups at positions 2 and 5, respectively. It is a pigment produced by Stveptomyces coelicolor. | undecylprodigiosin |
| veratrine | | Cevadine |
| verticine | | Verticine |
| vinburnine | | Eburnamonine |
| vinca | | LSM-18556 |
| vinpocetine | | Vinpocetine |