Li, H.R., V.V. Tertov, A.V. Vasil'ev, V.A. Tutel'yan, and A.N. Orekhov: Antiatherogenic 110 Li et al.suggesting that some mushroom species may be useful as dietary supplements in the prevention and therapy of atherosclerosis.

1,3-Diarylpropynones ArC≡CCOAr' in superacids with H 0 ranging from -20 to -14 undergo protonation at the carbonyl oxygen atoms to give stable ArC≡CC(O + H)Ar' ions or at the acetylenic C 2 atom with formation of reactive ArC + =CHCOAr' species. The effects of the Ar and Ar' substituents and reaction conditions on the intramolecular cyclization of ArC + =CHCOAr' to 3-arylinden-1-ones are discussed.

According to the 1 H and 13 C NMR data, 3-arylpropynoic acids and their esters XC 6 H n -C C-CO 2 R (R = H, Me, Et) having electron-withdrawing substituents in the benzene ring (X = NO 2 , CN, COMe, CO 2 Me) exist in HSO 3 F at -80 to 0°C as XC 6 H n -C C-C + (OH)OR ions. Derivatives with other substituents (X = H, F, Me, MeO) in HSO 3 F or CF 3 SO 3 H above -40°C undergo protonation at the acetylenic carbon atom neighboring to the acid group to give unstable vinyl-type XC 6 H n -C + =CH-CO 2 R cations which are then transformed into mixtures of stereoisomeric (Z and E) fluorosulfonates or triflluoromethanesulfonates XC 6 H n -CY=CH-CO 2 R (Y = OSO 2 F, OSO 2 CF 3 ), the E isomer prevailing.

No abstract

No abstract