Among the tasty assortment of delicacies associated with terpenes or terpenoids are citrus ( limonene ), black pepper ( sabinene ), ginger ( zingiberene and other sesquiterpenoids ), mint ( pulegone, although menthol is not an example ), cloves ( eugenol ), strawberry ( linalool and nerolidol ), among many, many others.
12.
Other terpenoids present only in traces are sabinene, ?-terpinene, 1, 8-cineole ( eucalyptol ), pulegone, ?-terpinene, terpineol-4-ol, bornyl acetate, ?-copaene, alloaromadendrene, viridiflorene, ?-bisabolene, ?-cadinene, trans-?-farnesene, trans-nerolidol, and ?-bisabolol.
13.
A wide variety of further routes continue to be explored, from early days until today, including total synthesis routes from ( " R " )-( + )-pulegone, semisyntheses from a more plentiful biosynthetic precursor, artemisinic acid in the latter case, including some very short and very high yielding biomimetic synthesis examples ( of Roth and Acton, and Haynes et al ., e . g ., 3 steps, 30 % yield ), which again feature the singlet oxygen ene chemistry.
14.
Geranyl diphosphate synthase ( GPPS ), first catalyzes the reaction of ( " )-limonene synthase ( LS ) catalyzes the cyclization of geranyl diphosphate to ( " )-limonene . ( " )-Limonene-3-hydroxylase ( L3OH ), using O 2 and NADPH, then catalyzes the allylic hydroxylation of ( " )-limonene at the 3 position to ( " )-trans-isopiperitenol . ( " )-Trans-isopiperitenol dehydrogenase ( iPD ) further oxidizes the hydroxy group on the 3 position using NAD + to make ( " )-isopiperitenone . ( " )-Isopiperitenone reductase ( iPR ) then reduces the double bond between carbons 1 and 2 using NADPH to form ( + )-cis-isopulegone . ( + )-Cis-isopulegone isomerase ( iPI ) then isomerizes the remaining double bond to form ( + )-pulegone . ( + )-Pulegone reductase ( PR ) then reduces this double bond using NADPH to form ( " )-menthone . ( " )-Menthone reductase ( MR ) then reduces the carbonyl group using NADPH to form ( " )-menthol.
15.
Geranyl diphosphate synthase ( GPPS ), first catalyzes the reaction of ( " )-limonene synthase ( LS ) catalyzes the cyclization of geranyl diphosphate to ( " )-limonene . ( " )-Limonene-3-hydroxylase ( L3OH ), using O 2 and NADPH, then catalyzes the allylic hydroxylation of ( " )-limonene at the 3 position to ( " )-trans-isopiperitenol . ( " )-Trans-isopiperitenol dehydrogenase ( iPD ) further oxidizes the hydroxy group on the 3 position using NAD + to make ( " )-isopiperitenone . ( " )-Isopiperitenone reductase ( iPR ) then reduces the double bond between carbons 1 and 2 using NADPH to form ( + )-cis-isopulegone . ( + )-Cis-isopulegone isomerase ( iPI ) then isomerizes the remaining double bond to form ( + )-pulegone . ( + )-Pulegone reductase ( PR ) then reduces this double bond using NADPH to form ( " )-menthone . ( " )-Menthone reductase ( MR ) then reduces the carbonyl group using NADPH to form ( " )-menthol.
