68000-79-3Relevant academic research and scientific papers
Regio- and Chemoselective Epoxidation of Fluorinated Monoterpenes and Sesquiterpenes by Dioxiranes
Lluch, Anna-Maria,Sanchez-Baeza, Francisco,Messeguer, Angel,Fusco, Caterina,Curci, Ruggero
, p. 6299 - 6308 (1993)
A comparative study on chemoselectivity of dimethyldioxirane (DMD) and methyl(trifluoromethyl)dioxirane (TFMD) in the epoxidation of trisubstituted C=C bonds presenting different activation in fluorinated monoterpene and sesquiterpene derivatives has been carried out.With respect to DMD, epoxidations performed with TFMD were faster under milder conditions, although high conversion yields were obtained with both reagents.In ease of epoxidation of unsaturated moieties the trend observed was: (CH3)(R1)C=CH(R2) ca. (CH3)(R1)C=CH(CH2OR) ca. (CH3)(R1)C=CF(R2) >> (CH3)(R1)C=CH(COOR) > (CF3)(R1)C=CH(R2).Results reported herein present the first example of direct epoxidation of a double bond bearing a CF3 substituent by non-biochemical means.Key Words: Epoxidation.Dimethyldioxirane; Methyl(trifluoromethyl)dioxirane.Chemoselectivity.Regioselectivity.Monoterpenes.Sesquiterpenes.
Substrate specificity for the epoxidation of terpenoids and active site topology of house fly cytochrome P450 6A1
Andersen, John F.,Walding, Jennifer K.,Evans, Philip H.,Bowers, William S.,Feyereisen, Rene
, p. 156 - 164 (2007/10/03)
Heterologous expression in Escherichia coli, purification, and reconstitution of house fly P450 6A1 and NADPH-cytochrome P450 reductase were used to study the metabolism of terpenoids. In addition to the epoxidation of cyclodiene insecticides demonstrated previously [Andersen et al. (1994) Biochemistry 33, 2171-2177], this cytochrome P450 was shown to epoxidize a variety of terpenoids such as farnesyl, geranyl, and neryl methyl esters, juvenile hormones I and III, and farnesal but not farnesol or farnesoic acid. P450 6A1 reconstituted with NADPH-cytochrome P450 reductase and phosphatidylcholine did not metabolize α-pinene, limonene, or the insect growth regulators hydroprene and methoprene. The four geometric isomers of methyl farnesoate were metabolized predominantly to the 10,11-epoxides, but also to the 6,7-epoxides and to the diepoxides. The 10,11-epoxide of methyl (2E,6E)-farnesoate was produced in a 3:1 ratio of the (10S) and (10R) enantiomers. Monoepoxides of methyl farnesoate were metabolized efficiently to the diepoxides. Methyl farnesoate epoxidation was strongly inhibited by a bulky substituted imidazole. The active site topology of P450 6A1 was studied by the reaction of the enzyme with phenyldiazene to form a phenyl-iron complex. Ferricyanide-induced in situ migration of the phenyl group showed formation of the N-phenylprotoporphyrinporphyrin IX adducts in a 17:25:33:24 ratio of the N(B):N(A):N(C):N(D) isomers. These experiments suggest that metabolism of xenobiotics by this P450, constitutively overexpressed in insecticide-resistant strains of the house fly, is not severely limited by stereochemically constrained access to the active site.
Use of dimethyldioxirane in the preparation of epoxy derivatives related to insect juvenile hormones
Messeguer,Sanchez-Baeza,Casas,Hammock
, p. 1291 - 1302 (2007/10/02)
A study on the epoxidation of methyl farnesoate using the title reagent has been carried out. In addition, dimethyldioxirane has shown to be a convenient reagent for the synthesis of putative metabolites of juvenile hormone III, such as diepoxide 4, triepoxide 5 and epoxy diol 7. This reagent has also shown to be an excellent tool for performing the preparation of tritium labelled derivatives 4 and 7. Finally, molecular mechanics and NMR studies for the characterisation of cis and trans tetrahydrofuran derivatives 8a and 8b, compounds resulting from the acid or enzymatic hydrolysis of epoxy diol 7, are also reported.
ON THE COHERENCE OF INCORPORATION OF THE FLUOROVINYL MOIETY INTO BIOACTIVE ORGANIC COMPOUNDS. SYNTHESIS OF AN INSECT JUVENILE HORMONE III FLUORINATED ANALOG.
Camps, F.,Messeguer, A.,Sanchez, Francisco-Jose
, p. 5161 - 5168 (2007/10/02)
An insect juvenile hormone fluoroanalog, methyl 10-fluoro-10,11-epoxyfarnesoate (9), has been prepared, using tandem Claisen-Cope rearrangements on fluorovinyl intermediate 1 as a crucial step.Along this synthesis chemical and spectral data have been obtained that might question some applications of fluorovinyl derivatives in the design of bioactive organic compounds.
