Investigations of 2,3′-biquinolyl. 9. Reaction of 1′,4′-dihydro-2,3′-biquinolyl with organolithium compounds

The 1,4-dihydro-2,3-biquinolyl reacts with organolithium compounds to form the mixture of 4-R-1,4-dihydro-2,3-biquinolyls and 2-R-1,2-dihydro-2,3-biquinolyls in the ratio analogous to the conversion in the series of 2,3-biquinolyl. The utilization of the complex, the organolithium compound-TMEDA, in this process leads, after treatment of the reaction mixture with water, exclusively to 2-R-1,2-dihydro-2,3-biquinolyls. Treatment with methyl iodide leads to 1-methyl-2-R-1,2-dihydro-2,3-biquinolyls.     

Resolution and Crystal Structure of 9α-(3-Azabicyclo[3,3,1]nonanyl)- 2′-cyclopentyl-2′-hydroxyl-2′-thienylacetate

1 INTRODUCTION The design, development and marketing of new chiral drugs are now a major theme in the drug chirality research and industry[1]. In 1996, the FDA announced it would consider further incentives for developing single isomer drugs because of their bet- ter pharmacokinetics prosperity, safety, and tolera- bility. Our recent drug candidate, 9α-(3-azabicyclo- [3,3,1]nonanyl)-2?-cyclopentyl-2?-hydroxyl-2?-thien- ylacetate I, is a potential selective M1 antagonist. It is composed…     

Host selectivity behaviour of trans-N,N′-bis(9-phenyl-9-xanthenyl)cyclohexane-1,2-diamine and trans-N,N′-bis(9-phenyl-9-thioxanthenyl)cyclohexane-1,2-diamine when presented with six-membered heterocyclic guest mixtures

Two compounds, trans-N,N′-bis(9-phenyl-9-xanthenyl)cyclohexane-1,2-diamine (1,2-DAX) and trans-N,N′-bis(9-phenyl-9-thioxanthenyl)cyclohexane-1,2-diamine (1,2-DAT), were assessed for their host ability in the presence of four heterocyclic guest species, namely pyridine (PYR), piperidine (PIP), morpholine (MOR) and dioxane (DIO). Each of these guests formed single solvent complexes with both host compounds. When 1,2-DAX and 1,2-DAT were recrystallized from various guest mixtures, it was shown that their selectivity orders were identical, DIO (46.6%)?>?MOR (23.0%)?>?PYR (18.9%)?>?PIP (11.5%) and DIO (85.9%)?>?MOR (23.7%)?>?PYR (8.9%)?>?PIP (8.5%), respectively, but that the thio host derivative possessed a significantly enhanced preference for DIO compared with its oxygen analogue. Additional experiments in order to investigate the various parameters at play in these complexation experiments involved single crystal diffraction experiments and thermal analyses.

     

Synthesis of N,N′-di(tert-butyl)bispidin-9-ones

Condensation of 1,3,5-tri(tert-butyl)-1,3,5-triazacyclohexane with acetone gave 3,7-di(tert-butyl)-1,5-bis[(tert-butylamino)methyl]bispidin-9-one. Reactions with ethyl methyl ketone and other ketones of the formula RCH₂COCH₃ yielded 5-R-3,7-di(tert-butyl)-1-[(tert-butylamino)methyl]bispidin-9-ones, while reactions with diethyl ketone and other symmetrical ketones of the formula RCH₂COCH₂R afforded 1,5-R-3,7-di(tert-butyl)bispidin-9-ones.     

6,6′-Dibromo-3,3′-dimethoxy-2,2′-dihydroxy-1,1′-biphenyl: preparation and resolution

A pratical route to prepare the title biphenyl 1 starting from 3,3′,2,2′-tetramethoxy-1,1′-biphenyl 2 is described. Resolution of 1 was achieved by its conversion into the corresponding diastereomeric menthyldicarbonate. The absolute configuration of (P)-(+)-1 was confirmed by X-ray analysis of the related diastereomer.     

Synthesis of 1′-substituted 4′,4′-dimethyl-6′-methoxy-4′H-spiro[cyclohexane-1,3′-isoquinolines]

The reaction of 1-(4-methoxyphenyl)-1-(1-methylcyclohexyl)ethanol with nitriles in concentrated sulfuric acid afforded 1′-substituted 6′-methoxy-4′,4′-dimethyl-4′H-spiro[cyclohexane-1,3′-isoquinolines] as a result of consecutive Wagner-Meerwein rearrangement and Ritter reaction.     

Synthesis and Structure of Tetraphenylantimony Oximates Ph4SbON=CRR′ (CRR′ = C6H9−C6H9-2 and R = Ph,R′ = C(O)Ph)

The reaction of pentaphenylantimony and the oxime HON=CRR taken in 1 : 1 molar ratio in toluene gave tetraphenylantimony oximates Ph₄SbON=CRR (CRR = C₆H₉–C₆H₉-2 (I) and R = Ph, R = C(O)Ph (II)). According to X-ray diffraction data, the Sb atoms in I and II have a distorted trigonal-bipyramidal coordination with oximate ligands in the axial positions. The C_axSbO angles are 177.6(1)° in I and 176.58(6)° in II. The Sb–C bond lengths lie in the ranges of 2.120(4)–2.203(4) Å for I and 2.122(2)–2.181(2) Å for II. The Sb–O bond lengths are 2.120(2) Å (I) and 2.166(1) Å (II). The lengths of the intramolecular Sb···N contacts are 2.806(3) and 2.918(2) Å in I and II, respectively.     

Synthesis of 5,5′-Dialkyl-6,6′-dichloro-2, 2′-bipyridines

5,5′-Dialkyl-6,6′-dichloro-2,2′-bipyridines were synthesized starting from 3-substituted 2-chloro-6-iodopyridines using Pd-catalyzed coupling conditions. 6-Alkyl-3,5-dichloro-2H-1,4-oxazin-2-ones were excellent precursors for the synthesis of these functionalized 2-iodo-6-chloropyridines.     

1，9-双（1′-苯基-3′-甲基-5′-氧代吡唑-4′-基）-壬二酮-[1，9]与含氮中性配体对镨（Ⅲ）的协同萃取

研究了 1,9 双 (1′ 苯基 3′ 甲基 5′ 氧代吡唑 4′ 基 )壬二酮 [1,9](H2 A)与含氮中性萃取剂 (B) ,如1,10 菲啉、2 ,9 二甲基 4 ,7 二苯基 1,10 菲啉、5 硝基 1,10 菲啉、2 ,2′ 联吡啶和 4 ,4′ 联吡啶 ,对镨 (Ⅲ )的协同萃取行为 ,确定了协萃配合物组成为PrA·HA·B ,求出了协同萃取平衡常数 ,制得了固态协萃络合物 ,并用元素分析、IR、UV、TG DTA对其组成和性质进行了表征。     

Spectral and kinetic investigation of interaction of 3,3′-diethyl-9-chlorothiacarbocyanine perchlorate with DNA

Interaction of the meso-substituted carbocyanine dye 3,3′-diethyl-9-chlorothiacarbocyanine (DCTC) perchlorate with DNA in phosphate buffer solutions (pH 7) was studied by spectral and kinetic methods. It was shown that the dye mainly exists in the cis-isomer form in water and aqueous-alcoholic solutions. The interaction with DNA leads to the formation of a trans-DCTC complex, which gradually (over a few tens of minutes) converts into the complex of the dye cis-isomer. It was revealed that the reactant concentration and ionic strength of solution have a considerable effect on the kinetic characteristics of trans-cis-reorganization of DCTC complexes, thus indicating a complex character of the process.     

Die indikatoreigenschaften des vicinalen m-Xylenolphthaleins (3′ ,5′ ,3′' ,5′'-Tetramethylphenolphthalein)

Ohne ZusammenfassungMit 1 Abbildung     

2′-5′连接寡聚核苷酸——2′-5′A核的固相合成

本文用磷酸三酯法,在交联聚丙烯酰吗福啉载体上,以1,3,5-三甲苯磺酰氯(MS)加N-甲基咪唑(N-Mein)为缩合剂,合成了2′-5′相连的寡聚腺苷酸——2′-5′A核。每个保护的单体接到载体上的收率是令人满意的,分别是100％,64％和89％。在合成过程中,我们对合成一系列中间体和制备载体的方法进行了改进,使产物收率大大提高,分离操作得以简化。     

Investigations of 2,3′-biquinolines 23. Synthesis of 1′-R-1′,4′-dihydro-2,3′-biquinolin-4′-ones by Claisen condensation

A method has been developed for the synthesis of 1′-R-1′,4′-dihydro-2,3′-biquinolin-4′-ones based on the interaction of quinaldine with N-alkyl-N-formylanthranilic acid methyl esters under the conditions of the Claisen condensation. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 409–410, March 2008.     

Improved Synthesis of 4,4′-Disubstituted-2,2′-Bipyridines

Ruthenium(II) tris(2,2′-bipyridine) complexes show interesting photochemical properties^1. Complexes containing substituents in the 4-and 4′-position of the 2,2′-bipyridine ligand have recently been used in systems which are aimed at the conversion and storage of solar energy^2,3. 2,2′-Bipyridine has a long history as a metal-chelating agent⁴. The use of 4,4′-disubstituted bipyridines as metal-chelating agents so far has been restricted probably because the reported syntheses of these compounds are rather laborious and the yields are low or moderate^5–8.     

Methoxyl-induced fluorescence quenching in N,N′-bridged 9H-dipyrrinones and an X-ray crystal structure

Strongly fluorescent dipyrrinones can be prepared by bridging the pyrrole and lactam nitrogens with a carbonyl group, from reaction with N,N′-carbonyldiimidazole in the presence of a strong, non-nucleophilic base. The yellow, N,N′-carbonyl-bridged dipyrrinones typically have fluorescent quantum yields (φ_F) approaching 1.0. Thus, in chloroform, N,N′-bridged 9H-dipyrrinones with β-alkyl substituents: 2,3-diethyl-7,8-dimethyl has φ_F = 0.90 (λ_em = 465 nm) and 2,3-dimethyl-7,8-dimethoxy has φ_F = 0.84 (λ_em = 482 nm). In contrast, 2,3-dimethoxy-7,8-dimethyl and 2,3,7,8-tetramethoxy show red-shifted λ_em but with strongly reduced φ_F: φ_F = 0.10 (λ_em = 511 nm) and 0.08 (λ_em = 511 nm), respectively. Methoxy substituents on the lactam, but not the pyrrole ring act to quench the fluorescence and shift the emission and excitation wavelengths bathochromically. The first X-ray crystal structure of an N,N′-carbonyl-bridged dipyrrinone was obtained from 7,8-dimethoxy-2,3-dimethyl-10H-dipyrrin-1-one. Correspondence: David A. Lightner, Department of Chemistry, University of Nevada, Reno, Nevada 89557-0020, USA.     

Microwave promoted one-pot synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl)coumarins

A facile procedure for the synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl)coumarins are being reported starting from 3- acetylcoumarin,aromatic aldehydes and malononitrile.The reactions were carded out on microwave irradiation in good yield with short time and easy work-up.The structures of all the compounds have been confirmed on the basis of their analytical,IR,~1H NMR, and mass spectral data.     

Thermal analysis of 5′-deoxy-5′-iodo-2′,3′-O-isopropylidene-5-fluorouridine

The melting temperature, melting enthalpy, and specific heat capacities (C _p) of 5′-deoxy-5′-iodo-2′,3′-O-isopropylidene-5-fluorouridine (DIOIPF) were measured using DSC-60 Differential Scanning Calorimetry. The melting temperature and melting enthalpy were obtained to be 453.80 K and 33.22 J g^?1, respectively. The relationship between the specific heat capacity and temperature was obtained to be C _p/J g^?1 K^?1 = 2.0261 – 0.0096T + 2 × 10^?5 T ² at the temperature range from 320.15 to 430.15 K. The thermal decomposition process was studied by the TG–DTA analyzer. The results showed that the thermal decomposition temperature of DIOIPF was above 487.84 K, and the decomposition process can be divided into three stages: the first stage is the decomposition of impurities, the mass loss in the second stage may be the sublimation of iodine and thermal decomposition process of the side-group C₄H₂O₂N₂F, and the third stage may be the thermal decomposition process of both the groups –CH₃ and –CH₂OCH₂–. The obtained thermodynamic basic data are helpful for exploiting new synthetic method, engineering design, and commercial process of DIOIPF.     

Synthesis and Crystal Structure of 3′-Ethyl 5′-Methyl 1-Benzyl-4′-methyl-2-oxo-3′,4′-dihydrospiro-[indoline-3,2′-pyrrole]-3′,5′-dicarboxylate

The crystal structure of the title compound(C24H24N2O5, Mr = 420.45) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a = 8.991(1), b = 11.166(1), c = 11.169(1) , α = 91.413(2), β = 105.887(2), γ = 90.992(2)°, V = 1077.8(2) 3, Z = 2, Dc = 1.296 g/cm3, F(000) = 444, μ(MoKα) = 0.091 mm-1, the final R = 0.0466 and wR = 0.1507 for 4185 observed reflections(I 2σ(I)). The single-crystal X-ray diffraction data indicated intermolecular C(17)–H(17)O(4), C(5)–H(5)… O(4) hydrogen bonds and C–H…π interaction in the structure.