A Novel Method for Synthesizing 4,4′-Bis(hydroxymethyl)-2,2′-bipyridine

IntroductionSince C. W. Tang firstly reported theelectroluminescence of 8- hydroxyquinolinealuminium[1] ,much attention has been paid to themetal complexes as electro- luminescent materials.Based on a series of experimental data,it has beenknown that the electroluminescence of metalcomplexes with heterocyclic ligands containing Nand O elements mainly results from the tripletstatetransition.For some transitional metal complexes,there exist the transitions from metal to ligand( MLCT) at thei…     

Synthesis of 5′-deoxy-5′-[18F]fluoro-adenosine by Radiofluorination of 5′-deoxy-5′-haloadenosine Derivatives

5-Deoxy-5-[¹⁸F]fluoro-adenosine was synthesised by nucleophilic radiofluorination reactions of 5-deoxy-5-haloadenosines. The homogeneous isotope exchange in 5-deoxy-5-fluoro-adenosine was also investigated. The conversion of these reactions was found to be rather low and depends on the strength of the halogen-carbon bond: 0.248% for chloride-, 0.488% for bromide- and 1.070% for iodide-derivative; there was no reaction observed in the case of fluoro-compound.     

The application of copolymer-coated graphene oxide-Fe3O4 in the highly efficient synthesis of 2′-aminospiro[indeno[1,2-b]quinoxaline-11,4′-[4'H] pyran]-3′-carbonitrile and 2′-aminospiro[indeno-2,4′-[4'H]pyran]-3′-carbonitrile

A magnetic nanocomposite based on graphene oxide was prepared. Fe₃O₄ nanoparticles were loaded on graphene oxide sheets and GO-Fe₃O₄ was covered by aniline-pyrrole copolymer to afford poly(Py-co-Ani)@GO-Fe₃O₄. This nanocomposite was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, vibrating sample magnetometry, X-ray diffraction, thermogravimetric analysis, and X-ray photoelectron spectroscopy techniques, and its catalytic activity was evaluated in the multicomponent synthesis of 2′-aminospiro[indeno[1,2-b]quinoxaline-11,4′-[4'H]pyran]-3′-carbonitrile and 2′-aminospiro[indeno-2,4′-[4'H]pyran]-3′-carbonitrile derivatives. This magnetically separable catalyst is heterogeneous noncorrosive, highly efficient, and reusable.     

One Pot Synthesis of Some New Spiro[3H-Indol-3,5′(4′H)-[1,2,4] Oxadiazol]-2-Ones and Bis[Spiro[3H-Indol-3,5′(4′H)-[1,2,4] Oxadiazol]-2-Ones]

A facile preparation of the title compound by 1,3-dipolar cycloaddition reaction of benzonitrile oxides with isatin imines or isatin diimines, in excellent yield, are reported.     

Green Aspect for Multicomponent Synthesis of Spiro[4H-indeno[1,2-b]pyridine-4,3′-[3H]indoles]

An efficient, four-component reaction of isatin, 1,3-indanedione, ethyl acetoacetate, and ammonium acetate in ethanol/water (9:1) system furnished spiro[4H-indeno[1,2-b]pyridine-4,3′-[3H]indoles] at room temperature. Merits of the method are mild reaction conditions, simple workup procedure, and ambient temperature. The synthesized compounds exhibit excellent fluorescence properties.     

SYNTHESIS OF SPIRO [1,3-BENZODIOXOLE-2,4′-(3′H) QUINAZOLINES]

Abstract

In the present investigation, the authors could obtain a new series of spiranes (1) through the reaction of the high potential quinone tetrachloro-o-benzoquinone with 2-aryl-3-phenyl-3H-quinazoline-4-thiones. Thus, 2,3-diphenyl- (2a), 2-p-tolyl-3-phenyl- (2b) and 2-p-anisyl-3-phenyl- (2c)-3H-quinazoline-4-thiones react readily with tetrachloro-o-benzoquinone, in boiling toluene, to give the corresponding spiro-1,3-benzodioxole-2,4′-(3′H)-quinazolines (1a-c), respectively.     

Synthesis and Investigation of Mass Spectra of 3-[5′-(2′-Substituent)thienyl]benzo[5,6]coumarins

3-[5'-(2'-Hydroxycarbonyl)thienyl]benzo[5,6]coumarin ( 3 ) was prepared via condensation of 2 with thioglycolic acid in the presence of AcONa and Ac 2 O. Esterification of 3 with alcohols gave 3-[5'-(2'-alkoxycarbonyl)thienyl]benzo[5,6]-coumarins ( 4a , b ). The chemical behavior of 4 toward nucleophilic reagents (such as ammonia, hydroxyl amine, and hydrazine derivatives) is described. The electron impact ionization mass spectra of compounds 4b , 5 , and 8a , b show a weak molecular ion peak and a base peak of m / z 278 resulting from a cleavage fragmentation. In contrest compounds 3 and 4a show a base peak of m / z 250 and m / z 74 resulting from fragmentation. Compounds 9 and 10 give a characteristic fragmentation pattern with a very stable fragment of m / z 305.     

A Novel Fluorescent Probe Based on Spiro[chromeno[2,3-c]pyrazole-4,1′-[2]benzofuran]-3′-one for Detecting Copper(II) ions in Aqueous Solution

Russian Journal of Organic Chemistry - A novel fluorescent probe, DHMP {7-(dibutylamino)-3-methyl-1H,3′H-spiro[chromeno[2,3-c]pyrazole-4,1′-[2]benzofuran]-3′-one} was designed and...     

Cu(II)-β-cyclodextrin-catalyzed synthesis of spiro[indoline-3,4′-pyrano[3,2-c]chromene]-3′-carbonitrile derivatives

Cu(II)-β-cyclodextrin-catalyzed synthesis of spiro[indoline-3,4′-pyrano[3,2-c]chromene]-3′-carbonitriles through the reaction of isatin derivatives, 4-hydroxycoumarin, and malononitrile in ethanol at room temperature.     

Aromatic 19F–13C TROSY—[19F, 13C]-Pyrimidine Labeling for NMR Spectroscopy of RNA

We present the access to [5-¹⁹F, 5-¹³C]-uridine and -cytidine phosphoramidites for the production of site-specifically modified RNAs up to 65 nucleotides (nts). The amidites were used to introduce [5-¹⁹F, 5-¹³C]-pyrimidine labels into five RNAs—the 30 nt human immunodeficiency virus trans activation response (HIV TAR) 2 RNA, the 61 nt human hepatitis B virus ϵ (hHBV ϵ) RNA, the 49 nt SAM VI riboswitch aptamer domain from B. angulatum, the 29 nt apical stem loop of the pre-microRNA (miRNA) 21 and the 59 nt full length pre-miRNA 21. The main stimulus to introduce the aromatic ¹⁹F–¹³C-spin topology into RNA comes from a work of Boeszoermenyi et al., in which the dipole-dipole interaction and the chemical shift anisotropy relaxation mechanisms cancel each other leading to advantageous TROSY properties shown for aromatic protein sidechains. This aromatic ¹³C–¹⁹F labeling scheme is now transferred to RNA. We provide a protocol for the resonance assignment by solid phase synthesis based on diluted [5-¹⁹F, 5-¹³C]/[5-¹⁹F] pyrimidine labeling. For the 61 nt hHBV ϵ we find a beneficial ¹⁹F–¹³C TROSY enhancement, which should be even more pronounced in larger RNAs and will facilitate the NMR studies of larger RNAs. The [¹⁹F, ¹³C]-labeling of the SAM VI aptamer domain and the pre-miRNA 21 further opens the possibility to use the biorthogonal stable isotope reporter nuclei in in vivo NMR to observe ligand binding and microRNA processing in a biological relevant setting.     

Synthesis of spiro[isoquinoline-4,4′-pyran]-3-imines

A method has been developed for the synthesis of 4-[2-(bromomethyl)phenyl] tetrahydro-2H-4-pyrancarbonitrile and a study was carried out on the reaction of this compound with primary amines, which, depending on the conditions, leads to either 4-[2-(R-aminomethyl)phenyl]tetrahydro-2H-4-pyrancarbonitriles or hydrobromides of 2-R-aryl-2,3,2,3,5,6-hexahydrospiro[isoquinoline-4(1H),4-pyran]-3-imines.Taras Shevchenko Kiev University, 252017 Kiev, Ukraine; e-mail: vkysil@mail.univ.kiev.ua. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1035–1041, August, 2000.     

MICROWAVE-INDUCED ONE-POT SYNTHESIS OF SOME NEW SPIRO[3H-INDOLE-3,5′(4′H)-[1,2,4]- TRIAZOLINE]-2-ONES

A rapid and efficient method for the synthesis of title compounds by 1,3-dipolar cycloaddition reaction or nitrilimines with isatin imines using microwave-induced and conventional methods is reported.     

A novel three-component method for the synthesis of spiro[chromeno [4′,3′:4,5] pyrimido[1,2-b] indazole-7,3′-indoline]-2′,6(9H)-dione

A green, efficient, and rapid procedure for the synthesis of novel spiro[chromeno[4′,3′:4,5] pyrimido[1,2-b]indazole-7,3′-indoline]-2′,6(9 H)-dione derivatives has been developed by one-pot condensation of 4-hydroxy-2H-chromen-2-one, isatin, and 1H-indazole-3-amine, in the presence of acetic acid in EtOH. This method has the advantages of operational simplicity, and high yield of products via a simple experimental and work-up procedure as compared to the conventional methods. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.     

Synthesis of spiro[furan-3,3′-indolin]-2′-ones by PET-catalyzed [3+2] reactions of spiro[indoline-3,2′-oxiran]-2-ones with electron-rich olefins

An efficient procedure for the synthesis of spiro[furan-3,3′-indolin]-2-ones and dispiro[cycloalkane-1,2′-furan-3′,3″-indolin]-2″-ones has been achieved in high yields and stereoselectivity by photoinduced electron transfer-catalyzed [3+2] reactions of substituted spiro[indoline-3,2′-oxiran]-2-ones with olefins. The reactions proceed by ring opening of spiro[indoline-3,2′-oxiran]-2-ones via C_β–O bond cleavage and subsequent cycloaddition with olefins by using 2,4,6-triphenylpyrylium tetarfluoroborate (TPT) as a sensitizer.     

棒丝氨酸的全合成研究 Ⅰ.从D-葡萄糖合成3-[(3′R,5′S)-7′-氧代-1′-氮杂-4′-氧杂双环[3.2.0]-庚-3′-基]-3-O-苄基-(2S,3S)-丝氨酸及其(3′R,5′R)-差向异构体

以D-葡萄糖为原料经侧链氨基酸合成,与β-内酰胺缩合,嗯唑烷环合和除保护基等反应合成了棒丝氨酸的O-苄基衍生物,3-[(3′R,5′S)-7′-氧代-1-氮杂-4-氧杂双环[3.2.0]-庚-3′-基]-3-O-苄基-(2S,3S)-丝氨酸(17)及其(3′R,5′R)差向异构体(18)。     

Synthesis of New 2′-(2- and 3-Aminopropanoyl)-6′,7′-dimethoxy-2′,3′-dihydro-1′H-spiro[cyclopentane-1,4′-isoquinoline]-1′-carboxamides

Russian Journal of Organic Chemistry - 6′,7′-Dimethoxy-N-methyl-2′,3′-dihydro-1′H-spiro[cyclopentane-1,4′-isoquinoline]-1′-carboxamide reacted with...     

Studies on the Cyclisation of 4-[2′-Cyclohexenyl]-3-hydroxy[1]benzopyran-2-one

The bicyclic coumarin derivative-1, 3 propano-2-bromo-1,2-dihydro-3H-pyrano [2, 3-c] [1]benzo-pyran-5-one (8) was synthesised by a sequence of reaction viz. acetylation of 4-[2′-cyclohexenyl] -3-hydroxy [1] benzopyran-2-one (4), addition of bromine to cyclohexenyl double bond and treating the resulting acetyldi-bromo derivative (7) with 4% alcoholic KOH. Benzofuro [2, 3-c] [1] -benzopyran-6-one (10) was synthesised from 4 via oxymercuration with mercuric acetate in methanol followed by dehydrogenative damercuration with Pd-C in refluxing diphenyl ether.     

5-[4-amino(1,2,5)oxadiazolyl]-5H-[1,2,3]tri-azolo [4,5-c][1,2,5]oxadiazole from 4,4′-diamino-3,3′-azofurazane

4,4-Diamino-3,3-azofurazane undergoes intramolecular oxidative cyclization to give 5-[4-amino(1,2,5)oxadiazolyl]-5H-[1,2,3]triazolo[4,5-c][1,2,5]oxadiazole upon heating with Pb(OAc)₄ in chlorobenzene oro-dichlorobenzene or with thionyl chloride.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 253–254, February, 1996.