Acyclic monoterpenoids nerol

Allylic alcohols [e.g. citronellol, geraniol (8), and nerol (18)] exhibit strong shielding at the y-carbon and deshielding at the 5-carbon in the 13C n.m.r. upon acylation.127 Cationic exchange resins separate acyclic [e.g. myrcene (12)] from cyclic (e.g. limonene) monoterpenoids.128... 

N.m.r. assignments for campholenic aldehyde, car-3-ene, /3-cyclocitral, three lavandulyl derivatives, and nerol oxide, as well as for 24 acyclic, 39 p-methane, six bicyclo[3,l,0]hexane, twelve bicyclo[2,2,l]heptane, and eight bicyclo[3,l,l]heptane monoterpenoids are recorded. ... 

The acyclic precursor of the monoterpenoids is normally assumed to be geranyl pyrophosphate (6 n = 1) but, clearly, this cannot directly cyclise to the foliamenthin skeleton. Two alternative precursors are" linalool pyrophosphate (28 R = P206 ) and nerol pyrophosphate (29 R = P206 ). Unfortunately,... 

The occurrence and syntheses of rose oxides, dihydrorose oxides, rosefuran, and nerol oxides, together with related compounds, have been reviewed. The structure of a cyclic monoterpenoid ether from Artemisia tridentata, which is related to the santolinyl monoterpenoids, has been confirmed (c/. Vol, 7, p. 20) as (227) and renamed artemiseole (c/. Vol. 8, p. 58 for an incorrect structural deduction).Interestingly, another new component of A. tridentata, the (3S)-diastereoisomer of (74), with formic acid yields (227) in contrast to (74) which yields the acyclic aldehyde (228). ° It is possible that some of the 31% of unidentified components in the essential oil of A. annua may correspond to these new compounds.The quinone (229) has been isolated from Lithospermum erythrofhizon, and further details on the presence of aeginetolide in Aeginetia indica have been published. 

Acyclic oxygenated monoterpenoids, e.g., nerol, geraniol, linalool, and cyclohexanoid congeners, e.g., a-terpineol, 1,8-cineole, camphor... 

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