Farrand, "Capsular polysaccharide biosynthesis and pathogenicity in Erwinia stewartii require induction by an N-acylhomoserine lactone
autoinducer," Journal of Bacteriology, vol.
168-170[degrees]C; IR (KBr, [cm.sup.-1]): 1720 (lactone
C=O), 1742 (methyl ester, C=O); [sup.1]H NMR (300 MHz, DMSO-[d.sub.6]): [delta] 2.40 (s, 3H, C[H.sub.3]), 3.85 (s, 3H, OC[H.sub.3]), 5.52 (s, 2H, OC[H.sub.2]), 6.85 (s, 1H, [C.sub.3]-H), 7.10-7.83 (m, 7H, Ar-H) ppm; Anal.
Impact of aging on lactones
is uniform as its amount showed a steady increase during sixteen months of storage.
Determination of moisture, pH, free acidity, lactones
and total acidity contents in honey
As addressed in other papers, we are of the opinion that the efficacy of GBE should be solely assigned to its terpene lactones
and not to flavonoids.
The 6-substituted compound 2 (R=Me, R1=H) has been used for the synthesis of pheromone methyl epijasmonate from lactone
1 via epoxidation .
In one study at an occupational dermatology clinic, 4.2% of 346 patients had positive reactions to the Compositae mix, whereas the sesquiterpene lactone
mix induced a positive reaction in 0.7% of 1,076 patients (Am.
Knowing that 1,3-dehydrohalogenation-cyclization is a diastereoselective process, the stereochemical structure of the eliminated, enantiomerically pure halolactones 3, 5, 7 was established from the configuration of chiral centers of the resulting bicyclic lactone
9, according to the mechanism presented in Scheme 2.
(8) These compounds include, but are not limited to, cis- and trans-oak lactone
, guaiacol, 4-methylguaiacol, eugenol, vanillin, furfural and 5-methylfurfural.
ptarmiciflorum lacks this sesquiterpene lactone
. Tanapsin was cytotoxic against leukemia and melanoma cells, including cells that overexpress Bcl2 and Bcl-[x.sub.L], with [IC.sub.50] values of approximately 10 [micro]M, but not against quiescent or proliferating human peripheral blood mononuclear cells.
Zhang, "AiiA, an enzyme that inactivates the acylhomoserine lactone
quorumsensing signal and attenuates the virulence of Erwinia carotovora," Proceedings of the National Academy of Sciences of the United States of America, vol.