Biosynthesis of tetrahydrocannabinolic acid  (THCA). In the first step, geranyl pyrophosphate and olivetolic acid form cannabigerolic acid, which is then enzymatically rearranged to THCA in the second step.   Cannabigerolic acid  (CBGA ) is the acidic form of cannabigerol  (CBG). It is a dihydroxybenzoic acid  and olivetolic acid  in which the hydrogen at position 3 is substituted by a geranyl group. It is a biosynthetic precursor to Delta-9-tetrahydrocannabinol , which is the principal psychoactive constituent of the Cannabis   plant. It is also a meroterpenoid  (i.e. a polyketide  and a terpenoid ), a member of resorcinols and a phytocannabinoid . It derives from an olivetolic acid. It is a conjugate acid of a cannabigerolate.[ 1]   
In the Cannabis  plant, olivetolic acid and geranyl diphosphate  are synthesized into CBGA.[ 2] : 6  [ 3] : 17    CBGA is converted in the plant by CBCA synthase, CBDA synthase  and THCA synthase  into CBCA , CBDA  and THCA  respectively.[ 2] : 6–7    
 
References    
Phytocannabinoids  (comparison )
Cannabibutols Cannabichromenes Cannabicyclols Cannabidiols Cannabielsoins Cannabigerols Cannabiphorols Cannabinols  CBN  CBNA  CBN-C1  CBN-C2  CBN-C4  CBNM   CBND    CBNP   CBVD     Cannabitriols Cannabivarins Delta-3-tetrahydrocannabinols Delta-4-tetrahydrocannabinols Delta-7-tetrahydrocannabinols Delta-8-tetrahydrocannabinols Delta-9-tetrahydrocannabinols Delta-10-Tetrahydrocannabinols Delta-11-Tetrahydrocannabinols Miscellaneous cannabinoids Active metabolites 
Endocannabinoids Synthetic cannabinoid receptor agonists / neocannabinoids 
Classical cannabinoids (dibenzopyrans) Non-classical cannabinoids Adamantoylindoles Benzimidazoles Benzoylindoles Cyclohexylphenols Eicosanoids Indazole-3- carboxamides Indole-3-carboxamides Indole-3-carboxylates Naphthoylindazoles Naphthoylindoles Naphthoylpyrroles Naphthylmethylindenes Naphthylmethylindoles Phenylacetylindoles Pyrazolecarboxamides Tetramethylcyclo- propanoylindazoles Tetramethylcyclo- propanoylindoles Others 
Allosteric  CBR Tooltip Cannabinoid receptor  ligands Endocannabinoid enhancers (inactivation inhibitors) Anticannabinoids (antagonists/inverse agonists/antibodies) 
  
TRPA 
Activators  4-Hydroxynonenal   4-Oxo-2-nonenal   5,6-EET   12S-HpETE   15-Deoxy-Δ12,14 -prostaglandin J2   α-Sanshool  (ginger , Sichuan  and melegueta peppers )  Acrolein   Allicin  (garlic )  Allyl isothiocyanate  (mustard , radish , horseradish , wasabi )  AM404   ASP-7663   Bradykinin   Cannabichromene  (cannabis )  Cannabidiol  (cannabis )  Cannabigerol  (cannabis )  Cinnamaldehyde  (cinnamon )  CR gas (dibenzoxazepine; DBO)   CS gas (2-chlorobenzal malononitrile)   Cuminaldehyde  (cumin )  Curcumin  (turmeric )  Dehydroligustilide (celery )  Diallyl disulfide   Dicentrine  (Lindera   spp.)  Farnesyl thiosalicylic acid  Formalin   Gingerols  (ginger )  Hepoxilin A3   Hepoxilin B3   Hydrogen peroxide   Icilin   Isothiocyanate   JT-010   Ligustilide  (celery , Angelica acutiloba  )  Linalool  (Sichuan pepper , thyme )  Methylglyoxal   Methyl salicylate  (wintergreen )  N-Methylmaleimide   Nicotine  (tobacco )  Oleocanthal  (olive oil )  Paclitaxel  (Pacific yew )  Paracetamol (acetaminophen)   PF-4840154   Phenacyl chloride   Polygodial  (Dorrigo pepper )  Shogaols  (ginger , Sichuan  and melegueta peppers )  Tear gases   Tetrahydrocannabinol  (cannabis )  Tetrahydrocannabiorcol   Thiopropanal S-oxide  (onion )  Umbellulone  (Umbellularia californica )  WIN 55,212-2    Blockers 
TRPC 
TRPM 
TRPML 
TRPP 
TRPV 
Activators  2-APB   5,6-EET   9-HODE   9-oxoODE   12S-HETE   12S-HpETE   13-HODE   13-oxoODE   20-HETE   α-Sanshool  (ginger , Sichuan  and melegueta peppers )  Allicin  (garlic )  AM404   Anandamide   Bisandrographolide (Andrographis paniculata  )  Camphor  (camphor laurel , rosemary , camphorweed , African blue basil , camphor basil )  Cannabidiol  (cannabis )  Cannabidivarin  (cannabis )  Capsaicin  (chili pepper )  Carvacrol  (oregano , thyme , pepperwort , wild bergamot , others)  DHEA   Diacyl glycerol   Dihydrocapsaicin  (chili pepper )  Estradiol   Eugenol  (basil , clove )  Evodiamine  (Euodia ruticarpa  )  Gingerols  (ginger )  GSK1016790A   Heat   Hepoxilin A3   Hepoxilin B3   Homocapsaicin  (chili pepper )  Homodihydrocapsaicin  (chili pepper )  Incensole  (incense )  Lysophosphatidic acid   Low pH  (acidic conditions)  Menthol  (mint )  N-Arachidonoyl dopamine   N-Oleoyldopamine  N-Oleoylethanolamide   Nonivamide (PAVA)  (PAVA spray )  Nordihydrocapsaicin  (chili pepper )  Paclitaxel  (Pacific yew )  Paracetamol (acetaminophen)   Phenylacetylrinvanil   Phorbol esters  (e.g., 4α-PDD)  Piperine  (black pepper , long pepper )  Polygodial  (Dorrigo pepper )  Probenecid   Protons   RhTx   Rutamarin (Ruta graveolens  )  Resiniferatoxin  (RTX) (Euphorbia resinifera /pooissonii  )  Shogaols  (ginger , Sichuan  and melegueta peppers )  Tetrahydrocannabivarin  (cannabis )  Thymol  (thyme , oregano )  Tinyatoxin  (Euphorbia resinifera /pooissonii  )  Tramadol   Vanillin  (vanilla )  Zucapsaicin    Blockers 
See also:  Receptor/signaling modulators • Ion channel modulators