title: Novel synthesis, properties, and NAD+-NADH type redox ability of 1,3-dimethylcyclohepta[4,5]pyrrolo[2,3-d]pyrimidine- 2,4(1,3h)-dionylium ions annulated with additional pyrrolo[2,3-d]pyrimidine-1,3(2,4h)-dione and furan analogue, and their hydride adducts.
abstract: [reaction: see text] A convenient preparation of novel cations 11a,b+ x BF4(-) and 12a,b+ x BF4(-), which are derived from annulation of the 1,3-dimethylcyclohepta[4,5]pyrrolo[2,3-d]pyrimidine-2,4(1,3H)-dionylium ion with additional pyrrolo[2,3-d]pyrimidine-1,3(2,4H)-dione and a furan analogue, was accomplished by a novel oxidative cyclization of 1,7-dihydro-7-[1',3'-dimethyl-2',4'(1',3'H)-dioxo-6'-(phenylamino)-pyrimidin-5'-yl]-1,3-dimethyl-10-phenylcyclohepta[4,5]pyrrolo[2,3-d]pyrimidine-2,4(1,3H)-dione 9 and its furan-analogue by using DDQ or photoirradiation under aerobic conditions. Structural characteristics of 11a,b+ and 12a,b+ were clarified on inspection of the UV-vis and NMR spectral data as well as X-ray crystal analyses. The stability of cations 11a,b+ and 12a,b+ is expressed by the pK(R+) values that were determined spectrophotometrically to be 10.7-12.6. The electrochemical reduction of 11a,b+ x BF4(-) and 12a,b+ x BF4(-) exhibited reduction potential at -0.93 to -1.00 (V vs Ag/AgNO3). The first reduction potential of 11a+ was reversible due to steric hindrance of two phenyl groups. The photoinduced oxidation reaction of 11a,b+ x BF4(-) and 12a,b+ x BF4(-) toward some amines under aerobic conditions was carried out to give the corresponding imines (isolated by converting to the corresponding 2,4-dinitrophenylhydrazones) with the recycling numbers of 0.6-30.3. Furthermore, as an example of the NAD+-NADH models, the reduction of a pyruvate analogue and some carbonyl compounds with the hydride-adduct of 11a+ x BF4(-) was accomplished for the first time to give the corresponding alcohol derivatives.
authors.affiliation: Department of Chemistry, School of Science and Engineering, Waseda University, Shinjuku-ku, Tokyo 169-8555, Japan.
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Naya
authors.forename: Junya
authors.initials: J
authors.lastname: Nishimura
authors.forename: Makoto
authors.initials: M
authors.lastname: Nitta
mesh_terms: D018360:Crystallography, X-Ray; D005663:Furans / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009243:NAD / Q000737:chemistry*; D010084:Oxidation-Reduction; D011743:Pyrimidines / Q000138:chemical synthesis* / Q000737:chemistry; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D005663:Furans; D011743:Pyrimidines; D011758:Pyrroles; D009243:NAD