Synthesis of some new heterocyclic systems derived from 2-acetylbenzimidazole

The named compound was reacted with thiosemicarbazide and/or semicarbazide to produce the corresponding condensation products II and V respectively. Reaction of II with chloroacetic acid in ethanol containing anhydrous sodium acetate yielded III. Condensation of III with aromatic aldehydes yielded the corresponding arylidene derivatives (IV). Oxidation of the semicarbazone V with selenium dioxide gave 2-(1,2,3-selenadiazole-4-yl)benzimidazole (VIa, b) while with thionyl chloride it gave 2-(1,2,3-thiadiazole-4-yl)benzimidazole (VIIa, b). The chalcones of 2-acetyl and/or 1-methyl-2-acetylbenzimidazole were condensed with hydrazine hydrate, phenylhydrazine and/or hydroxylamine to produce 2-(5-aryl-1(H)-pyrazolin-3-yl)-, 2-(5-aryl-1-phenyl-2-pyrazolin-3-yl)- and 2-(5-aryl-2-isoxazolin-3-yl)benzimidazole (IX, X, XI) respectively.     

New Bitopic Ligands for the Group Actinide Separation by Solvent Extraction

Abstract

The synthesis and evaluation of solvent extraction performance of N,N,N′,N′-tetraalkyl-6,6″-(2,2′:6′,2″-terpyridine)diamides and N,N′-diethyl-N,N′-diphenyl-6,6″-(2,2′:6′,2″-terpyridine)diamide are reported here. These new bitopic ligands were found to extract actinides in different oxidation states (U(VI), Np(V and VI), Pu(IV), Am(III), and Cm(III)) from 3 M nitric acid. The presence of three soft nitrogen donors led to the selective extraction of actinides(III) over lanthanides(III) (Ce, Eu) and the presence of two amide functional groups grafted to the terpyridine unit allowed the extraction to occur from a highly acidic medium by minimizing the basicity of the ligand. Ligands bearing long alkyl chains (C4 and C8) or phenyl groups showed increased performances in a polar diluent like nitrobenzene.     

Iodoazide addition to olefinic esters and their reaction with methanolic KOH

Addition of iodine azide to methyl 10-undecenoate (1), methyl oleate/elaidate (III,IV) and methyltrans-2-hexadecenoate (VII) yielded methyl 10-azido-11-iodoundecanoate (II, ∼ 100%), methylerythro/threo-9(10)-azido-10(9)-iodooctadecanoate (V,VI) and methylerythro-3-azido-2-iodohexadecanoate (VIII), respectively. The reaction of iodoazide adduct (II) with methanolic KOH yielded 10-azidoundec-10-enic acid (IX) and 10-oxoundecanic acid (X), while V and VI gave a mixture of 9(10)-oxooctadecanoic acid (XI). Adduct VIII, under the identical condition after esterification, gave 3 products, methyl 4-methoxy-trans-2-hexadecenoate (XII), 2-oxopentadecane (XIII) and methyl 3-methoxyhexadecanoate (XIV). The unusual behavior of VIII can be tentatively attributed to the role of adjacent carbonyl on the expected elimination of HI by methanolic alkali.     

Study of the mechanism of the antioxidant action of ethoxyquin

A study has been carried out of the reaction of 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline (ethoxyquin, I ) with alkylperoxyls. In the presence of a relatively low concentration of 1-cyano-1-methylethylperoxyl, I reacts to form dimer IV (8-(6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinolin-1-yl)-6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline) as the main product and quinoline derivative III (2,4-dimethyl-6-ethoxyquinoline), as a side product, i.e., substances formed by the conversion of the aminyl II (6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinolin-1-yl) alone. Smaller amounts of p-quinoneimine VI and o-quinoneimine VIII (2,2,4-trimethyl-2,6-dihydro-6-quinolone and 6-ethoxy-2,2,4-trimethyl-2,8-dihydro-8-quinolone) have been found; these substances are formed by further oxidation of II . In the presence of relatively high concentrations of tert-butylperoxyls, peroxide IX (6-tert-butylperoxy-6-ethoxy-2,2,4-trimethyl-2,6-dihydroquinoline) is formed as the main product. Substance IX thermally decomposes to form VIII , while in the presence of weak acids IX is converted into VI as the main product. Dimer IV is a medium-strength antioxidant which is gradually converted into 8-(6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinolin-1-yl)-2,2,4-trimethyl-6-quinolone (XI) and 8-(6-ethoxy-3-hydroxy-2,2-dimethyl-4-methylene-1,2,3,4-tetrahydroquinolin-1-yl-)-2,2,4-trimethyl-2,6-dihydro-6-quinolone) (XII) . The methyl group in XI actively participates in the antioxidation process. When formed, nitroxide V (6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinolin-N-oxyl) acts as an efficient antioxidant which, however, does not participate in the cyclic mechanism that is employed to explain the action of antioxidants of the HALS type. The antioxidant properties were evaluated on the basis of their effect on the course of the autoxidation of squalene.     

Synthesis of 4,4′-aryldihydrazono-3-(3′-pyridyl)-2-pyrazolin-4,5-diones and 1-aryl-3-(3′-pyridyl)-4,4′-arylbisazo-5-aryliminopyrazoles and their application as disazo disperse dyes. Part II

3-(3′-Pyridyl)-2-pyrazoline-4,5-dione 4,4′(4,4′-biphenylenedihydrazone and p-phenylenedihydrazone) and its derivatives ( IIa-e, IIIa-e ) were obtained by the coupling reaction of tetrazotised benzidine and p-diamonobenzene with 3-(3′-pyridyl)-2-pyrazolin-5-ones ( Ia-e ). Similarly, bis-azo compounds containing pyrazole nucleous as, 1-aryl-3-(3′-pyridyl)-4,4′-arylbisazo-5-aryliminopyrazoles ( VIa-i and VIIa-i ) were prepared by the interaction of the corresponding chloro compound ( IV and V ) with aromatic amines. The compounds so obtained ( II, III, VI and VII ) are used as disazo disperse dyes for dyeing polyester fibres fast yellow-orange shades. Their fastness properties towards washing, rubbing, acid-alkaline perspiration and light were investigated.     

3,1′-Bridged 2-[2′-(4″-dialkylaminophenyl)ethenyl] pyrylium and 1-Benzopyrylium Dyes – Synthesis and Vis/NIR Absorption/Emission Behaviour

A series of new 3,1′-bridged 2-[2′-(4″-dialkylaminophenyl)ethenyl]-4,6-diarylpyrylium perchlorates ( 3 ), 2-[2′-(4″-dialkylaminophenyl)ethenyl]-7-diethylamino-1-benzopyrylium perchlorates 5–8 , 2-[4′-(4″-dialkylaminophenyl)butadien-1′,3″-yl]-, and 2-[2′-(7″-diethylaminocoumar-3″-yl)ethenyl]-7-diethylamino-1-benzopyrylium perchlorates 10–12 were synthesized and characterized by means of elemental analysis, m.p., Vis/NIR, and ¹H NMR spectra. Semiempirical MO calculations were performed to elucidate the essential features of the chromophores. The size of the bridging ring strongly affects the geometry of the chromophores which, in turn, determines the extent of charge transfer of the longest wavelength electronic transition. Increasing deviation from planarity causes the polymethine-like chromophore to become more polyene-like.     

Synthesis of 2-alkyl-3-methyl-2-cyclopentenones from carboxylic acids or methylketones

Various 2-alkyl-3-methyl-2-cyclopentenones were prepared via 2-alkyl-4-penten-2-ols serving as common intermediates from carboxylic acids or methylketones. For example, dihydrojasmone was prepared from heptanoic acid as follows: Grignard reaction of heptanoic acid (I) with allylmagnesium chloride gave 1-decen-4-one (II) and re-Grignard reaction of (II) with methylmagnesium iodide produced 4-methyl-1-decen-4-ol (IV). 4-Methyl-1,4-decanediol (V) was obtained by hydroboration of (IV). Oxidation of (V) with chromium trioxide gave 4-hexyl-4-methyl-4-butanolide (VI). Dihydrojasmone may be prepared by dehydration of (VI) with polyphosphoric acid. Several new 2-alkyl-3-methyl-2-cylopentenones were obtained by this method.     

系列三联吡啶衍生物的合成及在催化氧化中的应用

采用一步法合成了5种三联吡啶的衍生物:4′-(吡啶-4-基)-2,2′∶6′,2″-三联吡啶(L1)、4′-苯基-2,2′∶6′,2″-三联吡啶(L2)、4′-(3,5-二氯吡啶-4-基)-2,2′∶6′,2″-三联吡啶(L3)、4′-(3,5-二溴吡啶-4-基)-2,2′∶6′,2″-三联吡啶(L4)、4′-(4-(吡啶-4-基)苯基)-2,2′∶6′,2″-三联吡啶(L5),其中L3和L4为尚未见报道的新颖化合物。以制备的多吡啶化合物为配体,和MnCl₂·4H₂O共同催化苄基醇的氧化反应,研究发现5种多吡啶配体均具备良好的性能,配体分子结构中的4′-吡啶取代基对提高催化活性有重要作用。最后选用性能最优的4′-(4-(吡啶-4-基)苯基)-2,2′∶6′,2″-三联吡啶为配体,与MnCl₂·4H₂O共同催化叔丁基过氧化氢氧化苄基醇和苄基烷烃,5种典型底物的转化率均在95%以上,产率在90%以上。该催化氧化方法有望应用于芳香酮类化合物及相关药物中间体的绿色、高效合成。     

The alkaline hydrolysis of methacrylates

The hydrolysis of a number of methacrylates in a 2,5% water-alcoholic solution of sodium hydroxide at 25°C was investigated. The hydrolysis of the ester group in 2-(N-methylanilino)ethyl(III), 3- and 4-dimethylaminobenzyl-(IV, V)-2-carboxyphenyl (VI) and 2,2,2-trichloroethyl (VII) methacrylate proceeded at approximately the same rate as in methyl methacrylate (I) and dimethylaminoethyl methacrylate (II); within 25 min, some 80% of the original esters were hydrolyzed. In alkaline solutions of 1,2,2,2-tetrachloroethyl (VIII), 2-(1,2,2,2-tetrachloroethoxy)ethyl (IX) and 1-(4-chlorophenyl)-2,2,2-trichloroethyl(X) methacrylates, the rate of hydrolysis of the ester group is decreasing in the order VIII>IX>X. The hydrolysis of the ester group was characterized by the rate constants of second order.     

Derivatization of keto fatty acids,Part IX. Synthesis and characterization of oxathiolanes

Oxathiolanes are prepared from the condensation of the oxo fatty acids with β- mercaptoethanol using BF₃etherate as catalyst. 10-Oxoundecanoic acid (I) reacts with the reagent promptly and gives 1-(ethylene oxathiolane) undecanoic acid (V). A similar reaction of 9-oxooctadecanoic acid (II) yields 9-(ethylene oxathiolane) octadecanoic acid (VII). Hemimercaptals (VI, VIII) are also isolated as minor products in the above reactions. Methyl 9,10-dioxooctadecanoate (III) is also found to react readily and affords methyl 9(10)- (ethylene oxathiolane)- 10(9)oxooctadecanoate (IX) as the sole product. There is no reaction with 2-oxooctadecanoic acid (IV). The spectral (infrared, nuclear magnetic resonance, mass) properties of oxathiolanes are detailed.     

Synthesis and antibacterial activity of thioglycolic amino acid derivatives and dipeptides containing the 2-methyl-3,4-dihydroquinazolin-4-one moiety

3-(2′-Chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one ( I ) was reacted with sodio (sodium thioglycolate) in dry dioxane and yielded compound II . By using thionyl chloride, this compound was converted to the corresponding acid chloride ( III ). The prepared acyl chloride ( III ) was allowed to interact with different α-amino acids such as Gly, L -Ala, L -B-Phe, DL -Asp, L -Glu, L -Thr and L -Val to give new amino acid derivatives ( IVa – g ). A selected C-terminal derivative of glycine ( IVa ) was converted into acid chloride ( V ). The acid chloride formed was reacted with L -Ala, L -B-Phe, DL -Asp, L -Glu, L -Thr and L -Val and yielded the new dipeptides VIa – f . The structures of the synthesized compounds were elucidated by elemental analysis and IR spectra. The prepared peptides were tested for their antimicrobial activities by comparison with tetra-cycline as a reference compound.     

Synthesis of some new diarylsulphides and diarylsulphones containing a quinazol-4-one moiety

4-Amino-4′-nitrodiphenylsulphide and 4-amino-2′-nitrodiphenyl sulphide ( I ) were smoothly condensed with 2-methyl-3,1-benzoxazin-4-one ( II ) to produce the corresponding 2-methyl-3-diphenylsulphidoquinazol-4-ones ( III ). 2-Styryl-3-diphenylsulphidoquinazol-4-ones ( IV ) were prepared by heating III with the appropriate aromatic aldehydes using piperidine as a basic catalyst. Compounds IV oxidised easily in a hydrogen peroxide-glacial acetic acid mixture to produce the corresponding sulphones ( V ). The constitution of some of the prepared products is discussed in the light of their infrared and ultraviolet spectra. The biological activities of some of these compounds were tested.     

Synthesis of fatty 2-oxazolines from fatty methyl 2,3-epoxy ester

Reaction of methyltrans-2,3-epoxyhexadecanoate (I) with benzonitrile in presence of boron trifluoride-etherate (BF₃-etherate) as catalyst has yieldedcis-2-phenyl-4-tridecyl-5-carbomethoxy-2-oxazoline (II), methyl 2-hydroxy-3-benzamidohexadecanoate (IV) and methyl 2,3-dihydroxyhexadecanoate (III). On the other hand, reactions of I with acetonitrile and acrylonitrile have resulted in the formation of their corresponding hydroxyamides, methyl 2-hydroxy-3-acetamidohexadecanoate (VI) and methyl 2-hydroxy-3-acryloamido hexadecanoate (VII), respectively, along with the product (III) only. Pyrolysis of hydroxyamides (IV), (VI) and (VII) afforded their corresponding 2-oxazolines,cis-2-phenyl-4-tridecyl-5-carboxy-2-oxazoline (V),cis-2-methyl-4-tridecyl-5-carboxy-2-oxazoline (VIII) andcis-2-vinyl-4-tridecyl-5-carboxy-2-oxazoline (IX), respectively, in good yields. The products have been characterized with the help of spectral and microanalyses. Presented at the 4th Annual Convention of the Indian Council of Chemists held in December 1984 at Gorakhpur University, India.     

Synthesis of some new 3-(2′-heterocyclicethyl)-2-methyl-3,4-dihydroquinazolin-4-one derivatives as antimicrobial agents

3-(2′-Chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one was reacted with acetylacetone, ethyl acetoacetate and diethylmalonate in the presence of sodium ethoxide to afford the alkylation products IV, V and VI , Compounds IV, V and VI were reacted with hydrazine hydrate, phenylhydrazine, hydroxylamine hydrochloride, urea and thiourea to yield 3-(2′-heterocyclicethyl)-2-methyl-3,4-dihydroquinazolin-4-one derivatives VII-XV . The structures of the synthesized compounds were elucidated by elemental analyses and spectroscopic (IR and XH-NMR) analyses. The prepared compounds were tested for their antimicrobial activities in comparison with tetracycline as a reference compound.     

Synthesis and antibacterial activity of certain quinoline and quinazoline derivatives containing sulfide and sulfone moieties

Some aryl and/or heterocyclic mercaptans were allowed to react with 8-quinolyl chloroacetate (II), 8-quinolinoxyacetyl chloride (IV) and 3-(2′-chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one (X) in dry benzene and/or sodium hydroxide in absolute ethanol to give corresponding 8-quinolyl-α-mercaptoacetate (V), 8-quinolinoxythioacetate (VI) and 3-(2′-arylmercaptoethyl)-2-methyl-4-(3H)quinazolin-4-ones or 3-(2′-heterocyclicmercaptoethyl)-2-methyl-4(3H)-quinazolin-4-ones (XIa-h). The mercaptans V and XI were subjected to oxidation with hydrogen peroxide/acetic acid mixture (1:2) to afford the corresponding sulfones VII and XII. The structures of the synthesized compounds were elucidated by spectroscopic (IR and ¹H-NMR) and elemental analyses. Some of these compounds were tested for their antimicrobial activities in comparison with tetracycline as a reference compound.     

4’-氯-2-（1H-1，2，4-三唑-1-基）苯乙酮的合成

以无水氯化铝为催化剂,氯苯和氯乙酰氯为原料,氯化铝与氯乙酰氯的物质的量之比为1．3：1,在45℃条件下反应3-4h,生成2-氯-1-（4-氯苯基）乙酮,产率可达87％;然后再以2-氯-1-（4-氯苯基）乙酮和1,2,4-三唑为原料,用摩尔数为1,2,4-三氮唑3％的四丁基溴化铵为相转移催化剂,45℃下反应4～5h,可得到68％的4’-氯-2-（1H-1,2,4-三唑-1-基）苯乙酮。     

Studies on the Vilsmeier-haack reaction. Part XIII: Novel heterocyclo-substituted 4,4′-bi-pyrazolyl dithiocarbamate derivatives

5-Imino-3-methyl-l-phenyl-2-pyrazoline-4-dithiocarbamic acid (I) underwent simultaneous formylation and dimerization reactions with the Vilsmeier reagent giving 4-[5′-imino-3-(1″-formyl-2″-dimethylaminoethenyl)-3′-methyl-1′-phenyl-1′H-pyrazolo-4′-dithiocarbamyl-2,4-dihydro-3-imino-5-methyl-2-phenyl-1-pyrazoline]dithiocarbamate (II) which hydrolysed with sodium hydroxide to give 4-[3′-(1″-formyl-2″-hydroxyethenyl)-3′-methyl-1-phenyl-1′-H-pyrazolo-4′-dithiocarbamyl-1′-pyrazoline]dithiocarbamate-5,5′-dione (IV). Treatment of II and/or IV with morpholine, piperidine, piperazine, hydroxylamine, hydrazine hydrate or phenylhydrazine afforded the corresponding dipyrazolo-4,4′-dithiocarbamate derivatives with different heterocyclic systems at the 3-position. The structures of these compounds were confirmed by microanalysis data, IR and ¹H-NMR spectrometry. All synthesized compounds have been screened in vitro against Gram-positive and Gram-negative bacteria, and fungi.     

手性烯唑醇为活性组分的杀菌聚合物的合成

以杀菌剂烯唑醇（Ⅰ）为底物,（-）-孟氧基乙酸为拆分试剂进行手性拆分,得到具有高杀菌活性的（R）-（E）-1-（2,4-二氯苯基）-2-（1,2,4-三唑-1-基）-4,4-二甲基-1-戊烯-3-醇（Ⅱ）。Ⅱ与丙烯酰氯反应生成了具有生物活性的可聚合单体（R）-（E）-1-（2,4-二氯苯基）-2-（1,2,4-三唑-1-基）-4,4-二甲基-1-戊烯-3-醇丙烯酸酯（Ⅲ）,Ⅲ经自聚或与丙烯酸或甲基丙烯酸甲酯共聚制得了杀菌聚合物（Ⅳ,Ⅴ,Ⅵ）,并进行聚合物活性组分的水解释放实验。总体上,在碱性介质中聚合物的活性组分水解释放速率大于在中性或弱酸性介质中的。Ⅳ和Ⅵ活性组分水解释放速率很低,而聚合物Ⅴ,随时间的延长,有大量的活性组分释出,初始释出质量浓度也较高,符合农用杀菌剂的速效性和持效性的要求,有实用意义。     

Photochemical Behaviour of Cyclopropa[c]Chromenes in Alcohols

Cyclopropa[c] chromenes (VI, VII, VIII, IX) on irradiation with a mercury high-pressure or low-pressure lamp in alcoholic solutions (MeOH, EtOH, i-PrOH) are transformed into the corresponding 2-(1′-alkoxy-but-3′-enyl)-phenols (cf. X, XI, trans. and cis-XII). Possible mechanisms of this photoreaction are discussed.     

Reaction of ketohexoses with acid in certain non-aqueous sugar solvents

Ketohexoses or potential ketohexoses react rapidly with acids at high temperatures in non-aqueous solvents (containing the grouping R·O·C·C·OH in their structures¹) to produce 5-hydroxymethyl-furfural (HMF). HMF reacts further to give the solvent ether (e.g., II, III or IV ) in a slow reaction. Several of these ethers have been reduced partially to mono-ethers of 2,5-di(hydroxymethyl)furan ( V, VI or VII ) and fully to mono-ethers of 2,5-di(hydroxymethyl)tetrahydrofuran ( VIII, IX or X ).