25519-55-5Relevant academic research and scientific papers
NaOH-Mediated Direct Synthesis of Quinoxalines from o-Nitroanilines and Alcohols via a Hydrogen-Transfer Strategy
Wang, Yan-Bing,Shi, Linlin,Zhang, Xiaojie,Fu, Lian-Rong,Hu, Weinan,Zhang, Wenjing,Zhu, Xinju,Hao, Xin-Qi,Song, Mao-Ping
, p. 947 - 958 (2021/01/14)
A NaOH-mediated sustainable synthesis of functionalized quinoxalines is disclosed via redox condensation of o-nitroamines with diols and α-hydroxy ketones. Under optimized conditions, various o-nitroamines and alcohols are well tolerated to generate the desired products in 44-99% yields without transition metals and external redox additives.
Methanol as a formylating agent in nitrogen heterocycles
Xu, Zhengbao,Zhang, Lizhi
, p. 9476 - 9482 (2021/11/17)
A radical mediated C-H direct formylation of N-heteroarenes with methanol is reported. The reaction features a novel iron-catalyzed Minisci oxidative coupling process using commercially available methanol as a formylating reagent. It effectively solved the long-standing problems associated with using methanol as a formylating reagent in these types of reactions. Compared to the traditional Minisci C-H formylation methods, this protocol is highly atom-economical, simple to operate, and environmentally friendly and shows good functional group tolerance. This Minisci formylation strategy is a straightforward approach for the late-stage functionalization of N-heteroarenes. This journal is
Copper-Catalyzed Aerobic Oxidation of Azinylmethanes for Access to Trifluoromethylazinylols
Zheng, Gang,Liu, Hao,Wang, Mang
supporting information, p. 519 - 523 (2016/06/01)
A copper-catalyzed oxygenation of methylazaarenes was found to occur in the absence of both ligand and additive, and has been successfully employed for the synthesis of trifluoromethylazinylketols. This synthetic strategy incorporates aerobic oxidation and a trifluoromethylation in one-pot and provides a novel method for the trifluoromethylation of aliphatic C-H bond.
An experimental and theoretical study of intramolecular regioselective oxidations of 6-substituted 2,3-dimethylquinoxaline derivatives
Peralta-Cruz, Javier,Díaz-Fernández, Mónica,ávila-Castro, Alberto,Ortegón-Reyna, David,Ariza-Castolo, Armando
, p. 5501 - 5515 (2016/07/06)
An experimental and theoretical study of the regioselective Riley oxidation was conducted on a series of 2,3-dimethyl-6-substituted-quinoxalines bearing EWG (NO2, CN, CF3, Cl, Br, F, COOH, COOMe, COPh) and EDG (2,3-dimethylquinoxaline, OMe, OH, NH2) substituents. The nitrogen lone pair of electrons of the symmetric benzopyrazine moiety initiates the oxidation and promotes nucleophilic competition between the two active sites to give carbaldehyde regioisomers a and b. The mesomeric effect provides the dominant contribution to the regioselectivity. The compounds were characterized by NMR, measuring the 1H, 13C, pfg-HSQC, pfg-HMBC, and 15N, 1H correlation signals established by pfg-HMQC. The nucleophilic reactivity of nitrogen was evaluated by 1H NMR titration and analyzed using Perrin linearization to determine the reactivity ratio, ΔK, of the N4 and N1 nitrogen atoms. The structures were optimized using density functional theory at the ωB97XD/6-311G++(d,p) level of theory. The highest occupied molecular orbitals modeled using the HF/6-311G++(d,p) functionals revealed an asymmetric electron density that confirmed the asymmetric nucleophilicity of the nitrogen centers. These values agreed with the experimentally measured ΔK ratios. The PM6 theoretical calculations of the heats of formation of the mesomeric forms and intermediates of (2,3-dimethyl-6-substituted-quinoxalines)-SeO2 allowed us to identify the reaction routes that minimized energy expenditures. The regioselectivities were explained in terms of the energetic diagrams of the regioisomers. All compounds evaluated indicated a preference toward forming regioisomer b, except for the derivative bearing the EDG substituent (2,3-dimethylquinoxaline) which displayed a preference for regioisomer a.
TRI-SUBSTITUTED PYRIMIDINE COMPOUNDS AND THEIR USE AS PDE10 INHIBITORS
-
Page/Page column 22, (2011/07/08)
The present invention provides a tri-substituted pyrimidine compound having an excellent PDE10 inhibitory activity. The present invention relates to a tri-substituted pyrimidine compound represented by the following formula [I0] or a pharmaceutically acceptable salt thereof, a method for preparing the same, and use of said compound for PDE10 inhibitor, and a pharmaceutical composition comprising said compounds as an active ingredient: wherein: either one of X1 and X2 is N, and the other of X1 and X2 is CH; A is *-CH═CH—, *-C(Alk)=CH—, *-CH2—CH2— or *-O—CH2— (* is a bond with R1); Alk is a lower alkyl group; Ring B is an optionally substituted nitrogen-containing aliphatic heterocyclic group; R1 is an optionally substituted quinoxalinyl or an optionally substituted quinolyl; Y0 is mono- or di-substituted amino group, or a pharmaceutically acceptable salt thereof.
Photochemistry of benzene and quinoxaline fused Δ2-1,2,3-triazolines and their trapping products
Chen, Yu-Jen,Hung, Hao-Chih,Sha, Chin-Kang,Chung, Wen-Sheng
experimental part, p. 176 - 182 (2010/03/04)
The benzene and quinoxaline fused Δ2-1,2,3-triazolines 1a and 1b were synthesized in good yields using Knoevenagel condensation and intramolecular 1,3-dipolar cycloaddition as two of the key reactions. Photolysis (254 nm) of Δ2-1,2,3-triazoline 1a or 1b in acetonitrile led to the homolytic cleavage of nitrogen that generated diethyl diazomalonate 7, highly reactive intermediates aziridines 8a,b, and isoindoles B. The latter two species subsequently underwent rearrangement to give the nitrogen extrusion products 9a,b, and polymers. Furthermore, the reactive intermediates were trapped by dienophiles to give the corresponding cycloadducts. Subsequent rearrangement of the N-bridged cycloadducts gave N-substituted pyrrolo[3,4-b]quinoxalines 12b and 15b in 6% and 9% yields, respectively. Irradiation of 1a in the presence of fumaronitrile led to the isolation of cycloadduct 16a with retention of stereochemistry. Thermal reaction of 1b gave more nitrogen extruded product 9b (58-63% yield) than that by photolysis (5-23% yield), which implied that zwitterionic intermediate might be involved in the former.
AROMATIC NITROGEN-CONTAINING 6-MEMBERED RING COMPOUNDS AND THEIR USE
-
Page/Page column 58; 59, (2010/04/06)
The present invention provides aromatic nitrogen-containing 6-membered ring compounds having execellent PDE10 inhibitory activity. The present invention relates to an aromatic nitrogen-containing 6-membered ring compound represented by the following formula [I0] or a pharmaceutically acceptable salt thereof, a method for preparing the same, and use of said compounds for PDE10 inhibitors, and a pharmaceutical composition comprising said compounds as an active ingredient: Formula [I0] wherein: X1, X2 and X3 each independently are N or CH, and at least two of X1, X2 and X3 are N; A is *-CH=CH-, *-C(Alk)=CH-, *-CH2-CH2- or *-O-CH2- (* is a bond with R1); Alk is a lower alkyl group; Ring B is an optionally substituted nitrogen-containing aliphatic heterocyclic group; R1 is an optionally substituted nitrogen-containing heterocyclic group, a nitrogen-containing heterocyclic moiety of which is a moiety selected from the group consisting of quinoxalinyl, quinolyl, isoquinolyl, quinazolinyl, pyrazinyl, pyrimidinyl and a moiety thereof fused with a 5 to 6-membered aliphatic ring thereto; Y0 is a group selected from the group consisting of the following (1) to (5): (1) an optionally substituted phenyl or an optionally substituted aromatic monocyclic 5 to 6-membered heterocyclic group; (2) an optionally substituted aminocarbonyl; (3) an optionally substituted amino lower alkyl; (4) -O-R2 wherein R2 is hydrogen, an optionally substituted lower alkyl, lower cycloalkyl, aliphatic monocyclic 5 to 6-membered heterocyclic group, or Formula [AA]; (5) mono- or di-substituted amino; provided that, when Y0 is mono- or di-substituted amino, the nitrogen-containing heterocyclic moiety of R1 is not quinoxalinyl or quinolyl.
CARBAMIC ACID COMPOUNDS COMPRISING A BICYCLIC HETEROARYL GROUP AS HDAC INHIBITORS
-
Page 99, (2010/02/08)
This invention pertains to certain carbamic acid compounds of the following formula, which inhibit HDAC (histone deacetylase) activity wherein: A is independently an unsubstituted or substituted bicyclic C9-10heteroaryl group (e.g., quinolinyl; quinoxalinyl; benzoxazolyl; benzothiazolyl); Q is an acid leader group, and is independently an unsubstituted or substituted, saturated or unsaturated C1 7alkylene group having a backbone length of 4 or less; with the proviso that if A is unsubstituted benzothiazol-2-yl, then Q is an unsaturated group; and with the proviso that if A is unsubstituted quinolin-6-yl, then Q is unsubstituted at the α-position; and with the proviso that A is not benzimidazol-2-yl; and pharmaceutically acceptable salts, solvates, amides, esters, ethers, chemically protected forms, and prodrugs thereof. The present invention also pertains to pharmaceutical compositions comprising such compounds, and the use of such compounds and compositions, both invitro and in vivo, to inhibit HDAC, and in the treatment of conditions mediated by HDAC, cancer, proliferative conditions, psoriasis, etc.
Oxidation of 2,3-Dimethyl-quinoxaline and 2,4-Dimethyl-quinazoline with Selenium Dioxide
Kepez, Mustafa
, p. 127 - 130 (2007/10/02)
The primary oxidation products of 2,3-dimethylquinoxaline with selenium dioxide are 3-methylquinoxaline-2-carbaldehyde, 1,3-dihydro-1,3-dihydroxyfuroquinoxaline and quinoxaline-2-carboxylic acid. 3-Methylquinoxaline-2-carboxylic acid can be obtained in a second oxidation step only. 2,4-Dimethylquinazoline is dehydrogenated by selenium dioxide to the heterocyclic stilbene derivative 8.Confirmation of structure of 8 is given by NMR spectroscopy. - Keywords: Oxidation of methyl groups; SeO2; Quinoxaline; Quinazoline
