Terpenoids Terpinen

Terpenes, specifically monoterpenes, are naturally occurring monomers that are usually obtained as by-products of the paper and citms industries. Monoterpenes that are typically employed in hydrocarbon resins are shown in Figure 2. Optically active tf-limonene is obtained from various natural oils, particularly citms oils (81). a and P-pinenes are obtained from sulfate turpentine produced in the kraft (sulfate) pulping process. Southeastern U.S. sulfate turpentine contains approximately 60—70 wt % a-pinene and 20—25 wt % P-pinene (see Terpenoids). Dipentene, which is a complex mixture of if,/-Hmonene, a- and P-pheUandrene, a- and y-terpinene, and terpinolene, is also obtained from the processing of sulfate Hquor (82). 

Terpenoid pheromones, 24 473 Terpenoid skeletons, 24 469 biosynthesis of, 24 471 Terpin hydrate, 3 231 a-Terpineol, 24 477, 509-512, 3 231 hydrogenation of, 24 512 a-Terpinyl acetate, 24 512 a-Terpinyl chlorides, 24 479 a-Terpinyl esters, 3 231 y-Terpinene, 3 230 Terpinolene, 24 493 Terpolymers... 

Heating (cooking) seems to produce certain terpenoids. In some vegetables, such as tomatoes and potatoes, there is a considerable increase in the formation of some terpene alcohols, including linalool, a-terpineol and terpinen-4-ol during heat treatments. 

Nutmeg Myristica fragrans (Myristicaceae) seed 5-16 sabinene (17-28) a-pinene (14-22) P-pinene (9-15) terpinen-4-ol (6-9) myristicin (4-8) elemicin (2) flavour, carminative, aromatherapy although the main constituents are terpenoids, most of the flavour comes from the minor aromatic constituents, myristicin, elemicin, etc myristicin is hallucinogenic (see page 385)... 

Defensive Compounds. Larvae of the weevil Oxyops vitiosa produce a shiny orange secretion that covers their integument and probably acts as deterrent against ants [420]. The composition of the secretion resembles the terpenoid pattern of the host foliage (Melaleuca quinquenervia) from where it is sequestered (concentration about twice that of the host foliage). It contains the sesquiterpene (+)-viridoflorol 230 (Scheme 25), the monoterpene hydrocarbons a-pinene 45, P-pinene 46, limonene 171, a-terpinene 231, and y-terpinene 232 as well as the oxygenated monoterpenesl,8-cineole 58, a-terpineol 233, and terpinen-4-ol 234. 

Figure 2. Structures of terpenoids chemically formed from linalool (1 ) at pH 3.5 (cf. Fig.1-4). (2) 2,4(8)-p-menthadiene (3) B-myrcene (4) a-phellandrene (5) cx-terpinene (6) limonene (7) B-phellandrene (8) (Z)-ocimene (9) y-terpinene (10) (E)-ocimene (11) p-cymene (12) terpinolene (13) (E,Z)-alloocimene (14) (E,E)-alloocimene (15) a-terpineol (16) 3,7-dimethyl-l-oct-ene-3,7-diol (17) 1,8-cineole (18) 2,2,6-trimethyl-2-vinyl-te-trahydropyran.

Scheme 6.7. A cartoon-like depiction of a possible path for the reaction of singlet oxygen ( 2) with a-terpinene, a conjugated terpenoid diene.

UnKke other citrus essential oils, tangerine essential oil contains about 0.85% of N-methyl methylanthranilic acid (8-187), which is the key component. Other important substances are terpenic hydrocarbons, such as y-terpinene and -pinene, terpenic aldehyde a-sinensal and other terpenoids. 

Research on the copolymerization of terpenoids with industrially used vinyl monomers or other monomers have been often reported. Littmann" introduced terpene-maleic anhydride resins for industrial use in alkyd resins in 1936. The resin was synthesized from a-terpinene and maleic anhydride via... 

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