首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
Methyl- and phenyl-substituted N-(ethoxycarbonyl)-2-azabicyclo[2.2.0]hex-5-enes 6 have been prepared by photoirradiation of appropriately substituted 1,2-dihydropyridines. Torquoselectivity is observed in the synthesis of the 3-endo-methyl- and 3-endo-phenyl-2-azabicyclo[2.2.0]hexenes 6c-e from 2-methyl- and 2-phenyl-1,2-dihydropyridines 5c-e. Products formed upon addition of bromine to 3-endo-, 4-, and 5-methyl- and 3-endo-phenyl-substituted N-(ethoxycarbonyl)-2-azabicyclo[2.2.0]hex-5-enes 6a-f were substituent dependent. For 6a,b, which lack substituents at C(3) or C(5), mixtures of unrearranged dibromides 8a,b and rearranged dibromides 9a,b were obtained. With the 3-endo-substituents in 6c-e, only rearranged dibromides 9c-e were formed; 5-methyl substitution afforded mainly unrearranged dibromide 8f and some allylic bromide 10. Both unrearranged 5-endo,6-exo-dibromo-2-azabicyclo[2.2.0]hexanes 8 and rearranged 5-anti-6-anti-dibromo-2-azabicyclo[2.1.1]hexanes 9 are formed stereoselectively. The dibromoazabicyclo[2.1.1]hexanes 9 have been reductively debrominated to afford the first reported 2-azabicyclo[2.1.1]hexanes 11 with alkyl or aryl substituents at C-3.  相似文献   

2.
8-Acetyl-7-aryl-2-arylmethylene-8,9-diaza- and 4,8,9-triazabicyclo[4.3.0]non-9-enes react with4-phenyl-4,5-dihydro-3H-1,2,4-triazole-3,5-dione, following the ene addition pattern. Under similar conditons 7-aryl-2-arylmethylene-8-methyl-8,9-diazabicyclo[4.3.0]non-9-enes give rise to both mono- and polyadditionproducts. The product structures were studied by 1H and 13C NMR, IR, and UV spectroscopy and singlecrystal X-ray diffraction.  相似文献   

3.
In previous studies we showed that 3-(substituted phenylethynyl)-5-methyl[1,2,4]triazine analogues of MPEP were potent antagonists of glutamate-mediated mobilization of internal calcium in an mGluR5 in vitro efficacy assay. In the present study we report the synthesis and evaluation of six 3-(substituted biphenylethynyl)-5-methyl[1,2,4]triazines (5a-f), and five 3-(substituted phenoxyphenylethynyl)-5-methyltriazines (6a-e). Compound 2-(4-fluorophenyl-5-[2-(5-methyl[1,2,4]triazine-3-yl)ethynyl]benzonitrile (5f) with an IC(50) of 28.2 nM was the most potent analogue.  相似文献   

4.
Six new N4-[bi-(4-fluorophenyl)-methyl]-piperazine thiosemicarbazones 3a-f have been prepared starting from [bi-(4-fluorophenyl)-methyl]-piperazine in solvent-free condition under microwave irradiation with excellent yields. Their structures have been determined by elemental analysis, IR, MS and 1H NMR data.  相似文献   

5.
(E,E)-Arylidene-beta-ionones (1a-f) are converted to 1,7,7-trimethyl-3-(E-2'-arylethenyl)-2-oxabicyclo[4.4.0]deca-3,5-dienes (3a-f, approximately 90%) by irradiating in anhydrous solvents. Irradiation of (3a-f) in aqueous methanol results in Z,E-arylidene-beta-ionones (2), through retro-electrocyclization, which undergoes an intramolecular, exo-selective [4 + 2] photocycloaddition leading to 11-(exo)-aryl-1,7,7-trimethyl-tricyclo[4.4.0.1(2,4)]undec-5-ene-3-ones (8a-f, 60-80%). The latter rearrange over silica gel to afford, quantitatively, 5-aryl-7,11,11-trimethyl-tricyclo[5.4.0.0(3,6)]undec-1-ene-4-ones (5a-f). Irradiation of 1a-f in aqueous methanol leads to 8a-f, except in case of 1c,f wherein formation, respectively, of tricyclic ketones 9c (55%) and 9f (80%), derived from photodeconjugation in 2, followed by intramolecular [4 + 2] cycloaddition, is observed.  相似文献   

6.
6-Alkylidene-2,3-benzo-1,4-diaza-7-oxabicyclo[4.3.0]non-2-enes were prepared by cyclization of 1,3-bis(silyl enol ethers) with quinoxaline.  相似文献   

7.
Convenient syntheses of 2-azafluorenones 5a-f and 5H[1]benzopyrano[3,4-c]pyridin-5-ones 6a-b were performed by using intramolecular cyclization of 4-arylnicotinic acids 4a-F. 4a-f were obtained via permanganate oxidation from the corresponding of 4-arylpyridines 3a-f in good yields.  相似文献   

8.
Methyl- and phenyl-substituted N-(ethoxycarbonyl)-2-azabicyclo[2.2.0]hex-5-enes 6 were reacted with NBS in wet DMSO to afford bromohydrins. Mixtures of unrearranged 6-exo-bromo-5-endo-hydroxy-2-azabicyclo[2.2.0]hexanes 7a,b and rearranged 5-anti-bromo-6-anti-hydroxy-2-azabicyclo[2.1.1]hexanes 8a,b were formed stereoselectively from the parent alkene 6a and 4-methyl alkene 6b. The 5-methyl alkene 6c affords only unrearranged bromohydrin 7c and dibromohydrin 9. By contrast, solely rearranged 3-endo-substituted-2-azabicyclo[2.1.1]hexane bromohydrins 8d-f result from additions to 3-endo-methyl alkene 6d, 3-endo-4-dimethyl alkene 6e, and 3-endo-phenyl alkene 6f. As an alternative route to bromohydrins, the parent 5,6-exo-epoxide 10a and 5-endo-methyl-5,6-exo-epoxide 10b were ring opened with bromine/triphenylphosphine to afford unrearranged 5-endo-bromo-6-exo-hydroxy-2-azabicyclo[2.2.0]hexanes 11a,b, while the 3-endo-methyl epoxide 10c afforded solely the rearranged 5-anti-bromo-6-anti-hydroxy-3-exo-methyl-2-azabicyclo[2.1.1]hexane isomer 8g. Tributyltin hydride reduction of bromohydrins 7a,b and 11a afforded novel 2-azabicyclo[2.2.0]hexan-5-ols 13a,b and -6-ol 14, and bromohydrins 8a,b, 8d-g afforded new 2-azabicyclo[2.1.1]-hexan-5-ols 15a,b and 15d-g.  相似文献   

9.
1,3-Diaza-6-oxabicyclo[3.1.0]hex-3-enes and their 3-oxides were obtained by the photolysis of 2H-imidazole 1-oxides and 2H-imidazole 1,3-dioxides. 1,3-Diaza-6-oxabicyclo [3.1.0]hex-3-ene 3-oxides are thermally unstable and are converted to the starting 2H-imidazole 1,3-dioxides; their further photolysis affords a mixture of stereoisomeric 1,3-diaza-4,7-dioxatricyclo [4.1.0.03,5]heptanes.For the previous communication, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2096–2100, December, 1993.  相似文献   

10.
[reaction: see text] Reactions of chalcones 3a-f with bis(1H-1,2,4-triazolyl) sulfoxide 4 formed the thiazolo[3,2-b]1,2,4-triazoles 5a-f, which resemble closely some previously prepared COX-2 inhibitors. The structure of 5a was confirmed by X-ray analysis.  相似文献   

11.
A series of novel benzo[b]thiophen-2-yl-3-(4-arylpiperazin-1-yl)-propan-1-one derivatives 6a-f, 7a-f and their corresponding alcohols 8a-f were synthesized and evaluated for their affinity towards 5-HT(1A) receptors. The influence of arylpiperazine moiety and benzo[b]thiophene ring substitutions on binding affinity was studied. The most promising analogue, 1-(benzo[b]thiophen-2-yl)-3-(4-(pyridin-2-yl)piperazin-1-yl)propan-1-one (7e) displayed micromolar affinity (K(i) = 2.30 μM) toward 5-HT(1A) sites. Docking studies shed light on the relevant electrostatic interactions which could explain the observed affinity for this compound.  相似文献   

12.
Furan compounds     
Electrolysis of monofurfuryl ethers of ethylene glycol in methanolic solution results in intramolecular alkoxylation, with the formation of the hitherto undescribed 2-methoxy-1, 6, 9 trioxaspiro-[4, 5]dec-3-enes. Catalytic hydrogentation of the latter at room temperature in the presence of Raney nickel catalyst gives 70–90% yields of the 2-methoxy-1, 6, 9-trioxaspiro[4, 5]dec-3-enes.For Part XLII, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, PP. 1155–1159, September 1970.  相似文献   

13.
Additions of iodonium-X reagents to N-alkoxycarbonyl-2-azabicyclo[2.2.1]hept-5-enes and the homologous 2-azabicyclo[2.2.2]oct-5-enes have been found to mirror the outcomes of additions of bromonium-X reagents. Only rearranged products were observed for reactions of either of these halonium ion reagents with the azabicylo[2.2.1]hept-5-enes. For the azabicyclo[2.2.2]oct-5-enes, nitrogen participation in addition of IOH or BrOH was dependent on the N-alkoxycarbonyl group. With larger N-Boc, N-Cbz, or N-Troc protecting groups, unrearranged 5-anti-hydroxy-6-syn-I(or Br)-2-azabicyclo[2.2.2]octanes were formed by nucleophilic attack at C(5) on syn-halonium ions. The structure of N-methyl-8-anti-bromo-4-anti-hydroxy-2-azabicyclo[3.2.1]octane has been reassigned by X-ray analysis.  相似文献   

14.
Chlorolactames 2a-f reacted with sodium azide to give the cyclopropylketimines 3a-f (75-89%), and acid hydrolysis of 3c,d yielded the cyclopropylketones 6c,d (61-67%). Compounds 3a-f and 6c, d were transformed by heating (170-240 degrees C, sublimation) to the air-sensitive dihydropyrroles 4a-f (51-71%) and dihydrofurans 7c, d (85-91%). Oxidation of the dihydro derivatives 4a-f and 7c,d with DDQ led to novel types of pyrrolo[3,2-e][1,4]diazepinedione derivatives 5a-f (75-84%) and furo[1H][3,2-e][1,4]diazepinediones 8c, d (91-93%).  相似文献   

15.
6-Thia-l-aza-5λ5-phosphabicyclo[3.2.0]hept-3-enes and Isothiocyanatophosphine-sulfides from (Methylidenamino)phosphines, Carbon Disulfide, and Acetylene- or Ethylene Derivatives (Methylidenamino)phosphines react with carbon disulfide to 1,3,2-thiazaphosphete derivatives 2 . Acetylenedicarboxylates give with 2 6-thia-l-aza-5λ5-phosphabicyclo[3.2.0]hept-3-enes 4a , b , and acrylates yield isothio-cyanatophosphin-sulfides 5a – c . The structures of 4a and 5a are proven by an X-ray diffraction analysis.  相似文献   

16.
New methods have been developed for the synthesis of pyrido[1,2-a]pyrazinium-1- and 3-olates 5a-f, 9 and 1-thiolate 24 as well as of pyrido[1,2-b]pyridazinium-4- and 2-olates 14, 20 . The methylation of these new compounds was studied by soft and hard methylating agents. Depending on the nature of the reagent used, the pyrido[1,2-a]pyrazinium-1-olates 5a-f gave NMe 22a-f and/or OMe 23a-f products, whereas the 3-olate 9 and both the 4- and 2-pyridazinium-olates 14, 20 afforded solely OMe compounds 10, 15, 21 . A selectivity rule for methylation is proposed.  相似文献   

17.
The synthesis of 4-triflyloxy-2,6,6-trimethyl-2,4-cyclohexadienone (13), bicyclo[2.2.2]octenones 1a-j and 15a-j, and bicyclo[2.2.2]octadienones 2a-f, 6a-d, and 11a-f is described. The 2,4-cyclohexadienones 4 and 13 were used for the first time as nondimerizing and easily accessible alternatives to 2,6,6-trimethyl-2,4-cyclohexadienone 12 in Diels-Alder reactions with acetylene derivatives 5a-d to prepare the adducts 6a-d and 11a-e in excellent yields. Compounds 11a-d were initially prepared by the alcoholysis of 6a-d to afford bicyclo[2.2.2]octene-2,5-diones 7a-dfollowed by treatment of 7a-d with N-phenyltriflimide in the presence of LHMDS at -78 degrees C. Diels-Alder reaction of 13 with an acetylene equivalent, phenyl vinyl sulfoxide, was also studied. A detailed study of the Diels-Alder reactions of various olefinic dienophiles 14a-j with 13 has been carried out to furnish cycloadducts 15a-j in high yields. Reductive removal of triflyloxy group of vinyl triflates 11a-f and 15a-j was performed in the presence of [Pd(PPh(3))(2)Cl(2)-Bu(3)N-HCO(2)H] to obtain the desired bicyclo[2.2.2]octadienones 2a-f and bicyclo[2.2.2]octenones 1a-j, respectively, in good overall yields.  相似文献   

18.
The new 2H,4H-[1]benzopyrano[3,4-b]pyridine-1,3,5-trione derivatives 10a-f were prepared in the following three steps: first the preparation of new N-(tert-butoxycarbonyl)-3-amino-2H-1-benzopyran-2-one derivatives 5a-f by reaction of coumarin-3-carboxylic acids and diphenylphosphorylazide, then hydrolysis of 5a-f with gaseous hydrogen chloride to give the corresponding amines 7a-f , and finally the preparation of 10a-f by reaction of 7a-f and carbon suboxide in the presence of a Lewis acid.  相似文献   

19.
Hydrolysis of ethyl 3-amino-4-aryl-cycloalka[e]thieno[2,3-b]pyridine-2-carboxylates ( 3a-d) gave the corresponding o-aminocarboxylic acids 4a-d . Heating the latter compounds ( 4a-d) with acetic anhydride furnished the oxazinone derivatives 5a-d which, in turn, underwent recyclization reaction to give the corresponding pyrimidinones 6a-d upon treatment with ammonium acetate in acetic acid. Reaction of 3-amino-4-aryl-cycloalka[e]thieno[2,3-b]pyridine-2-carboxamides ( 3f,h ) with triethyl orthoformate gave pyrimidinone derivatives 7a,b . Reaction of 3-amino-4-phenyl-cycloalka[e]thieno[2,3-b]pyridine-2-carboxamides 3e,h with aromatic aldehydes furnished tetrahydropyridothienopyrimidinones 8a-d . Chlorination of 7a,b and 6a-d by using phosphorous oxychloride produced 4-chlorocycloalka[5′,6′]pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine derivatives 9a-f which were used as key intermediates in the synthesis of several new cycloalkapyrido-thienopyrimidines 10a-f ˜ 14a-f . Moreover, some cycloalkapyridothienotriazinones 15a,b-17a,b were synthesized.  相似文献   

20.
N-Acylimines (2) possess the characteristics of both hetero-1,3-dienes and dienophiles. They react with the kinetically stabilised cyclobutadienes 1 to form 4-aza-2-oxabicyclo[4.2.0]octa-3,7-dienes (3) and/or 2-azabicyclo[2.2.0]hex-5-enes (4). Compounds of the type 3 undergo acid-catalysed isomerisation to give compounds 4. Homocyclopropenylium intermediates of the type 5 are supposed to be involved in both processes (1 + 2 → 3 + 4 and 3 → 4).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号