- Theoretical and Infrared Matrix Isolation Study of 4(3H)-Pyrimidinethione and 3(2H)-Pyridazinethione. Tautomerism and Phototautomerism
-
IR spectra of 4(3H)-pyrimidinethione and 3(2H)-pyridazinethione isolated in argon and nitrogen matrices are reported.The thiol and thione tautomeric forms of 4(3H)-pyrimidinethione were found in matrices in relative concentrations ca. 5:1.IR spectra of gaseous sample showed that the ratio of tautomers in matrices corresponds to the gas-phase tautomeric equilibrium.Only the thione form of 3(2H)-pyridazinethione was observed in matrices.UV-vis irradiation of the matrices caused the conversion ot the thione forms of the studied molecules into the thiol forms.The IR spectra of the thione and thiol tautomers were predicted theoretically a t SCF/3-21G* level, and a comparison ot the predicted and experimentally observed spectra enabled an assignment of most of the observed bands.
- Nowak, Maciej J.,Lapinski, Leszek,Fulara, Jan,Les, Andrzej,Adamowicz, Ludwik
-
-
Read Online
- GAMMA SECRETASE INHIBITORS
-
Disclosed herein are compounds of Formula (I) (I) and pharmaceutically acceptable salts thereof, wherein each of the substituents is given the definition as set forth in the specification and claims. Also disclosed are pharmaceutical compositions containi
- -
-
Page/Page column 23
(2013/03/26)
-
- Heterocyclic compounds
-
Compounds of formula (I): STR1 wherein R1, R2 and R3 are independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, alkylcycloalkyl, halogen, haloalkyl, alkoxy, alkenoxy, alkoxyalkyl, haloalkoxy, alkylthio, cyano, nitro, amino, NR5 R6, hydroxy, acylamino, --CO2 R4, --O(CH2)m CO2 R4, phenyl, phenoxy, benzyl or benzyloxy, the phenyl group or phenyl moiety of the benzyl group being optionally substituted in the ring; or R2 and R3 when taken together form a 5- or 6-membered ring; m is 1 or 2; R4 and R6 are hydrogen or C1-4 alkyl; R5 is C1-4 alkyl; n is 0, 1 or 2; are useful as nematicides.
- -
-
-