S-Linalool

S)-3,7-Dimethyl-2-oxo-6-octene-l,3-diol (39) was recently identified as the aggregation pheromone of the Colorado potato beetle (Leptinotarsa decem-lineata), and synthesized by Oliver et al., starting from (S)-linalool [86]. An improved synthesis of (S)-39 by Mori is shown in Scheme 57 [87]. Enzymatic acetylation of ( )-2,3-epoxynerol (A) with vinyl acetate and lipase PS gave B together with C. The acetate B was converted to a multi-gram quantity of (S)-39 according to Oliver [86]. 

Figure 12.6 Stereospecific biotransformation of (R,S)-linalool by C. cassiicola via the (6S)-configured epoxylinalools as postulated intermediates...

Dudareva N, Cseke L, Blanc VM, Pichersky E (1996) Evolution of floral scent in Clarkia Novel patterns of S-linalool synthase gene expression in the C. breweri flower. Plant Cell 8 1137-1148... 

Figure 10.1. The gene from Clarkia breweri coding for (S)-linalool synthase (LIS) was added to three different piant species (tomato, petunia and carnation) and each species produced the expected product, S-iinaiooi. However, the existing NP metabolic flexibility in each species aiiowed the novei substance, S-iinaiooi, to be converted to other substances, those substances being different in each species due to the differences in NP metabolism in each plant. ...

Fig. 17.14 Simultaneous stereoanalysis of Lavandula oil constituents, using enantio-MDGC (standard mixture), a Preseparation of racemic compounds unresolved enantiomeric pairs of octan-3-ol (6, 7), frcms-linalool oxide (1, 2), oct-l-en-3-ol (9, 10), ds-linalool oxide (3, 4), camphor (5, 8), linalool (17, 18), linalyl acetate (11, 12), terpinen-4-ol (15, 16) and lavandulol (13, 14). b Chiral resolution of enantiomeric pairs, transferred from the precolumn trans-linalool oxide 1 (2S,5S), 2 (2R,5R) ds-linalool oxide 3 (2R,5S), 4 (2S,5R) camphor 5 (IS), 8 (IR) octan-3-ol 6 R, 7S oct-1-en-3-ol PS, 10 R linalyl acetate 11 R, 12 S lavandulol 13 R, 14 S terpinen-4-ol 15 R, 16 S linalool 17 R, 18 S. [75]...

Not all attempts at metabolic engineering deliver the expected results. For example, Liicker et al. [11] transformed petunia (Petunia hybrida) with the (S)-linalool synthase (LIS) gene from Clarkia breweri (Scheme 26.1), but despite... 

The transformation of Arabidopsis thaliana with a cDNA from strawberry fruits encoding a dual (S)-linalool/(S)-nerolidol synthase also led to the production of both (S)-linalool and its glycosylated and hydroxylated derivatives in the leaves [14]. Surprisingly, the formation and emission of (S)-nerolidol was detected as well, suggesting that a small pool of its precursor farnesyl diphosphate is present in the plastids. The newly emitted (S)-linalool and (S)-nerolidol showed the same diurnal emission pattern as the pristine volatiles. 

Scheme 26.1 Catalytic formation of (S)-linalool from geranyl diphosphate. OPP denotes the diphosphate moiety...

Clavatin Claviformin Coriandrol Patulin Patulin S-Linalool... 

Fig. 5.1. A sample of floral scent compounds. (1) Substituted methyl esters of benzoic acid. The ester smells unpleasantly sweet when R = H (methyl benzoate), of wintergreen when R = OH (methyl salicylate), and of concord grape when R = NH2 (methyl anthranylate). Odorants with unusual origins and biological functions include the homoterpene 4,8-dimethyl-1,3,7-nonatriene (2) and the wet-earth compound geosmin (3). Some ubiquitous fragrance compounds are ben-zaldehyde (4), benzyl alcohol (5), indole (6), (S)-linalool (7), ( )-/ -ocimene (8), and of-farnesene (9).

Linalool (3,7-dimethyl-l,6-octadien-3-ol) (62) occurs as one of its enantiomers in many essential oils, where it is often the main component. (/ )-(-)-Linalool for example occurs at a concentration of 80-85% in Ho oils from Cinnamomum camphora rosewood oil contains ca 80%. (S)-(+)-Linalool makes up 60-70% of coriander oil [26]. 

Another example of fungal bioconversion of linalool was described in literature the biotransformation by Diplodia gossypina ATCC 10936 [61]. A conversion scheme for the bioconversion of both (/ )-(-)- and (S)-(+)-linalool was proposed. 

Decanol Geranial Neryl acetate ct s-Linalool oxide P-Caryophellene ... 

Oliver (2003) reported pure (S)-(+)-linalool from oil of coriander by formation and recrystallization of its 3,5-dinitroben-zoate ester, followed by regeneration and distillation. Fathima et al. (2001) noted that microwave drying affected the colour, appearance and odour properties of coriander. 

DUDAREVA, N., CSEKE L., BLANC, V.M., PICHERSKY, E., Evolution of floral scent in Clarkiar. Novel Patterns of S-linalool synthase gene expression in Clarkia breweri flowers., Plant Cell, 1996,8,1837-1848. 

Jasmine Jasminum grandiflorum Benzyl acetate, (S)-linalool, indole, (Z)-jasmone (27), (R,Z)-7-decen-5-olide (28), methyl (+)-ep/-jasmonate (29) 95,96,98... 

Coriander Coriandrum sativum (S)-Linalool, (-)-camphor, geraniol 95,100... 

Sweet orange Citrus sinensis (S)-Linalool, octanal, decanal, a//3-sinensal (65, 66) 95,96... 

Oxidation of the chiral (4-geranylseleno)-15-(4-toluenesulfonyl)[2.2]paracyclophane with 3-chloroperbenzoic acid gave (S )-linalool with 67% enantioselectivity39. Diethylamine was added before warming up to avoid side reactions by the generated selenic acid. On the basis of similar oxidation of paracyclophane-substituted alkyl selenides it was assumed that the asymmetric induction in the oxidation step is responsible for the modest selectivity. 

In the case of linalool the enantiomeric ratio was more variable between plants. In majority of investigated plants (R)-(-)-linalool dominates. The plants of the highest optical purity of (-)-Iinalool have been fovmd lavender Lavandula angustifolia), bergamot Citrus auranthium Bergamia), thyme Thymus vulgaris) and basil Ocimum basilicum). In a group of plants in which (S)-(+)-linalool dominates a practically pure enantiomer has been revealed in Robinia flowers Robinia pseudoacacia). 

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