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1.
Allene reacts with compounds of the type (β-diketonato)Ir(η-C8H14)2| (I) to give iridium(III) derivatives of formula (β-diketonato)IrC12H16 (II) in which an allene tetramer i.e. the 2,3,6,7-tetramethyleneoctane-1,8-diyl group, is bonded to the iridium atom by two η3-allylic groups. The molecular structures of these complexes were deduced by 1H NMR studies and by single-crystal X-ray analysis of (hfacac)IrC12H16 (IIb). The reactions of the complexes II with hydrogen and with CO are described.The reaction of (acac)Ir(η-C8H14)2 with allene, at -78°C, gives a thermally unstable compound of probable stoichiometry (acac)Ir(C3H4)4 (VI). Its low-temperature IR spectrum and its reaction with bromine indicate that VI contains two η2-bonded allene molecules and teh 3,4-dimethyleneiridocyclopentane moiety. VI reacts with pyridine with loss of an allene molecule to give an iridium(III) derivative of formula (acac)Ir(C6H8)(C3H4)py (IX). Complex IX was shown by single-crystal X-ray analysis to contain the 3,4-dimethyleneiridocyclopentane moiety and one η2-bonded allene molecule.The role of irido cycles as precursors of the bis(allylic) complexes II is discussed.  相似文献   

2.
The work involves synthesis of novel Schiff base derivatives containing a pyrimidine unit starting with chalcones. 4-Aminoacetophenone was reacted with 4-nitrobenzaldehyde or 4-chlorobenzaldehyde in basic medium giving chalcones, [I]a and [I]b, respectively, by Claisen-Schemidt reaction. The chalcones [I]a and [I]b were reacted with urea in HCl medium giving oxopyrimidines, [II]a and [II]b. They were also reacted with thiourea in basic medium to give thioxopyrimidines, [III]a and [III]b. The novel mono and bis Schiff bases, [VIII]na, [VIII]nb, [IX]na, [IX]nb, [X]na, [X]nb, [XI]na, and [XI]nb were synthesized by the reaction of pyrimidine derivatives; oxopyrimdines, [II]a and [II]b and thioxopyrimidines, [III]a and [III]b with 4-(4′-n-alkoxybenzoloxy)benzaldehyde [VI] and polymethylene-α,ω-bis-4-oxybenzaldehydes [VII]m, respectively, in dry benzene using drops of glacial acetic acid as a catalyst. The synthesized compounds were characterized by melting points, elemental analysis, FTIR, and 1H NMR spectroscopy.  相似文献   

3.
A novel and convenient method for the synthesis of eritadenine (I) was established. Direct condensation of adenine and 2,3-O-isopropylidene-D -erythronolactone (II) under basic condition, followed by removal of the protecting group, afforded eritadenine (I) in fairly good yield, with accompany of a small amount of the N3-isomer (VI). A similar reaction of adenine 1-oxide gave exclusively eritadenine oxide (VII), which was catalytically reduced to give eritadenine (I). This procedure also provided pyrimidinyl derivatives (VIII, IX and X) corresponding to cytosine, uracil, and thymine.  相似文献   

4.
2-Carboxy-1-alkylindole-3-acetic acid anhydrides (I) condensed with S-methylisothiosemicarbazide in DMF to form 5,11-dihydro-6-methyl-2-methylthioindolo[3′,2′:4,5]pyrido[1,2-b]-s-triazol-5-one (II). Compound II underwent ring opening on refluxing with sodium hydroxide solution to give IV. The anhydride I reacted with primary amines in benzene to give 2-carboxy-1-alkylindole-3-acetanilide derivatives (VI) which yielded l-methylindole-3-acetic acid by decarboxylation followed by hydrolysis. Compound II oxidised to the diketo compound X which could be prepared by the hydrolysis of the azomethine derivative IX with acetic acid-hydrochloric acid mixture. Compound II reacted with benzyl chloride to yield the dibenzyl derivative XII, condensed with p-chlorobenzaldehyde to form the 11-p-chlorobenzylidene derivative XI and coupled with arenediazonium salt to give the 11-arylhydrazone derivatives XIII.  相似文献   

5.
Thiazolecarboxylate esters (I) and (II) react with hydrazine hydrate to give the acid hydrazides (III) and (IV), which then react with KSCN and PhNCS to give high yields of the thiosemicarbazides (V)-(VIII). Cyclocondensation of the thiosemicarbazide (V) with 3-phenyl-3-chloro-2-oxopropionic acid derivatives gives compounds with two thiazole moieties (IX)-(XIV). The reaction of the phenylthiosemicarbazides (VII) and (VIII) with chloroacetyl chloride and (or) chloroacetic acid affords the thiazolidinonethiazoles (XV) and (XVI).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2832–2836, December, 1991.  相似文献   

6.
1-Alkyl-3-carboxyindole-2-acetic acid anhydrides (I) react with ethylenediamine and with o-phenylenediamine to give directly 10-alkylimidazo[3,2:1′,2′]pyrido[4,5-b]indol-5(1H)-ones (II) and 5,6-dihydro-5-alkyl-13H-indolo[2′,3′:4,5]pyrido[1,2-a]benzimidazol-13-one (V), respectively. However, anhydrides I react with o-aminophenol and with o-aminothiophenol to give carboxyindole-acetanilide derivatives IX, which can be cyclised to indolo[2′,3′:4,5]pyrido[2,1-b]benzoxazolone and indolo[2′,3′:4,5]pyrido[2,1-b]benzthiazolone (XI). Some derivatives of II and V were prepared to help in elucidating the structures.  相似文献   

7.
Methylglyoxalyl chloride arylhydrazones (III) react with an ethanolic solution of thiourea to give 2-amino-4-methyl-5-arylazothiazoles (XII) instead of the expected 2-acetyl-4-aryl-5-imino-Δ2-1,3,4-thiadiazolines (V) which were obtained from III and potassium thiocyanate. 3-Thiocyanato-2,4-pentanedione (IV) coupled with diazotized anilines to give V. The postulated routes to formation of V and XII from III are given. Nitrosation of V gave the corresponding N-nitroso derivatives (VI) which decomposed upon refluxing in dry xylene to give 2,4-disubstituted-Δ2-1,3,4-thiadiazolin-5-ones (VII). Boiling of either V or VI with hydrochloric acid gave the hydrochloride salt (VIII). The thiadiazolines V gave the respective N-acyl derivatives (IX) and (X) with acetic anhydride and benzoyl chloride in pyridine.  相似文献   

8.
Reaction of phenylglyoxalyl bromide arylhydrazones (III) with thiourea in ethanol produces 2-amino-4-phenyl-5-arylazothiazoles (XI) instead of the expected 2-benzoyl-4-aryl-5-imino-Δ2?1,3,4-thiadiazolines (V) obtained from III and potassium thiocyanate. Phenacyl thiocyanate (IV) couples with diazotized anilines to give V. The mechanisms of formation of V and XI from VI and III, respectively, are postulated. Nitrosation of V gives the corresponding N-nitroso derivatives (VII), which decompose upon refluxing in xylene to give 2,4-disubstituted Δ2 ?1,3,4-thiadiazolin-5-ones (VIII). The thiadiazolines V give the respective N-aeyl derivatives IX and X with acetic anhydride and benzoyl chloride in pyridine.  相似文献   

9.
Synthesis of (–)-(1R,2S)-Norephedrine Homologues The amino function of esters of some simple natural amino acids I is blocked in the form of a cyanoenamine by means of 2-oxocyclopentanecarbonitrile, so that the corresponding cyanoenamino esters II are obtained. The reaction of a disubstituted lithium amide with II leeds to the cyanoenamino-amides VI . The amide function present in VI is then transformed into an aromatic ketone by means of phenyllithium, to give the (benzoylalkyl)aminocyclopentenecarbonitriles VII . Reduction of Compounds VII with NaBH4 in EtOH ?80° affects only the keto function and leads to the [(α-hydroxybenzyl)alkyl]amino-cyclopentenecarbonitriles VIII . The amino function is then deprotected by acid hydrolysis to give the amino-alcohols IX with yields close to 50%; in every amino-alcohol IX , the erythro isomer, homologous to natural (–)-(1R,2S)-norephedrine is the more abundant or the single product. All the polyfunctional compounds prepared conserve optical activity; it has been demonstrated that the amino-alcohols IX are pure enantiomers and that no racemisation lakes place at any step of their synthesis.  相似文献   

10.
A series of aminothiazole derivatives have been synthesized by using ultrasmall superparamagnetic iron oxide nanoparticles (SPIONs) nanomagnetic catalysis, which were prepared by reducing the Fe(II) and Fe(III) precursors using aqueous ammonia then characterized by the XRD, FTIR, SEM, and TEM. The 2-aminothiazole derivatives were obtained by coupling 2-aminothiazole diazonium salt with active methylene compounds then cyclization with hydrazine hydrate to afford pyrazolyl derivatives. The one-pot reaction of 2-aminothiazole with an aromatic aldehydes in the presence of Fe3O4 NPs to give Schiff bases derivatives. An efficient protocol is developed proudest yields and reduction reaction time and easy separation. Therefore, all synthesized compounds were evaluated for anti-microbial activity.  相似文献   

11.
4-Chlorobenzenesulfonyl isocyanate (I) reacted with 2-chloroethanol and 1-chloro-2-propanol to give, respectively, 2-chloroethyl 4-chlorobenzenesulfonyl carbamate (III) and 1-chloro-2-propyl 4-chlorobenzenesulfonyl carbamate (VI). The carbamates III and VI cyclized under the influence of pyridine to afford, respectively, 3-(4-chlorobenzenesulfonyl)oxazolidin-2-one (IV) and 3-(4-chlorobenzenesulfonyl)-5-methyloxazolidin-2-one (VII). The oxazolidin-2-ones were stable toward hydrochloric acid but hydrolyzed in 2M sodium hydroxide solution to N-(2-hydroxyethyl)-4-chlorobenzenesulfonamide (V) and N-(2-hydroxy-1-propyl)-4-chlorobenzene-sulfonamide (VIII), respectively. 4-Toluenesulfonyl isothiocyanate (II) reacted with 2-chloroethanol to give 2-chloroethyl 4-chlorobenzenesulfonyl thiocarbamate (IX), which was converted by pyridine to 3-(4-toluenesulfonyl)oxazolidine-2-thione (X).  相似文献   

12.
Partial ammonolysis of silicon tetrachloride in diethylether below ?60°C gives hexachlorodisilazane (I; yield 40%), hexachlorocyclotrisilazane (II; 3–5%) and polychlorosilazanes, mainly [Cl2SiNH]x (III). For a survey of the single steps of this reaction, see scheme 2. Cleavage of III with HCl, HBr (in benzene or ether) or SiCl4 (elevated temperature and pressure) gives more I in moderate and octachlorotrisildiazane (IV) in very low yield. I reacts with butyllithium to lithium-bis(trichlorosilyl)amide (IX). This compound forms deutcrohexachlorodisilazane on reaction with heavy water and decomposes on heating into LiCl and decachloro-bis(silyl)-cyclodisilazane (XIX). Physical properties and analytical data of the conpounds are summarized in tables 2 and 3. Many other reactions of I, II and IX may be seen in chapter 4a, b as well as in schemes 3, 4 and 6.  相似文献   

13.
p-Tolyl 2-thienyl ketone (I) condensed with dimethyl succinate in the presence of potassium t-butoxide to give the trans (SC4H3/CO2Me) half-ester (IIIa) whose configuration was deduced by cyclization to the corresponding benzo[b]thiophene derivatives. Carbamates, esters, cyclic hydrazides and substituted phenolic and acetic acids useful as antibacterial and antiinflamatory agents were obtained. The reaction of ketone I with malononitrile to give ylidenemalononitrile II was also considered.  相似文献   

14.
Morphanthridines III with a basic substituent in position 6, which show neuroleptic activity, have been synthesised as follows: Chlorination of the lactams I with POCl3 gave the iminochlorides II, which were converted by bases to the amidines III. The 11-oxo-morphanthridines VI and VII were synthesised using the same procedure, 2-(1-methylpiperazine-4-carbonyl)-2′-amino-benzophenone (XI) was obtained directly from the 6-chloro-11-oxo-morphanthridine (V) or by extended heating of VI with N-methylpiperazine. Reduction of the 11-oxo-compounds VI and VII with NaBH4 gave the 11-hydroxy-compounds IX and X. 3-(2-aminophenyl)-phtalide (VIII) resulted from the acid hydrolysis of IX.  相似文献   

15.
The treatment of Z-1,1,3-trichloro-4,4-dimethyl-2-pentene (Ia) with t-C4H9OK in boiling hexane or benzene gave rise to (Z-2-chloro-3,3-dimethyl-1-butenyl)chlorocarbene (IVa), which reacted with alkenes to give the cyclopropane derivatives (V) in 44–57% yields. Dichloro-(2-chloro-1-alkenyl)methanes (Ib-d), which have a hydrogen atom at the C3 position of the alkenyl substituent, were also used as carbene precursors under these conditions. These compounds gave rise to mixtures of the cyclopropanes (VI)–(VIII) (obtained in up to 57% yields) and the dienes (IX)–(XI) (yields up to 54%). The reaction of cis-2-butene with (2-chloro-1-cyclopentenyl)chlorocarbene (IVd) was found to be completely stereospecific, indicating that this carbene exists in a singlet ground state.For previous communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2552–2558, November, 1991.  相似文献   

16.
Some new pyridazinone derivatives(3) were synthesized through addition of antipyrin to β-aroylacrylic acids (1) followed by cyclization of the adducts. Reactions of 3 with ethyl bromoacetate, benzenesulfonyl chloride, benzoyl chloride and POCl3 give N-substituted products and monochlorosubstituted pyridazines (4), respectively. The reactions of the latter with thiourea give unexpected dithio-derivatives (5), which react with phenylhydrazine to give pyrazolopyridazino pyridazine derivatives (6). Reactions of 2 with NH2OH in ethanol and pyridine afford oxime and oxazinone derivatives 7 and 8, respectively. The antibacterial activities of several compounds were screened.  相似文献   

17.
Abstract

3,5-Dicyano-6-mercapto-4-phenylpyridin-2(1H)-one (1) was reacted with ethyl chloroacetate to give compound (II) which on reaction with hydrazine hydrate gave the corresponding hydrazide derivative (III). Acylation of (III) with acetic acid, phenylisocyanate, or phenylisothiocyanate gave different monoacyl derivatives (IV-VI). Condensation of III with aromatic aldehydes and acetylacetone gave compounds VIIa-c, VIII respectively. Compound I was reacted with chloroanilides, bromoacetone and phenacyl bromide to yield the IX-XI; these and compound II gave thieno[2,3-b]-pyridines (XU-XV) on treatment with sodium ethoxide solution. Reaction of XII with acetic anhydride gave the diacetyl derivative XVI. Hydrolysis of compound XII with sodium hydroxide gave the corresponding acid (XVII) which on treatment with acetic anhydride gave the oxazine derivative (XVIII). Reaction of oxazine compound XVIII with ammonium acetate and hydrazine hydrate gave pyrido[3′,2′:4,5] thieno[3,2-d]pyrimidin-4.7-dione derivative (XIX) and (XX) respectively. The N-amino derivative (XX) was reacted with 4-nitrobenzaldehyde to give the corresponding azomethine (XXI).

Significant in vitro gram-positive and gram negative antibacterial activities as well as anti-fungal effect were observed for some members of the series.  相似文献   

18.
The simple one-pot reaction of protoporphyrin IX and omega-(N-imidazolyl)alkylamine or O-methyl-L-histidyl-glycine with benzotriazol-1-yl-oxytris(dimethylamino)phosphonium hexafluorophosphate at room temperature produced a series of protoporphyrin IX species with a covalently linked proximal base at the propionate side-chain. The central iron was inserted by the general FeCl2 method, converting the free-base porphyrins to the corresponding protoheme IX derivatives. Mesoporphyrin IX and diacetyldeuteroporphyrin IX analogues were also prepared by the same procedure. The Fe(II) complexes formed dioxygen (O2) adducts in dimethylformamide at 25 degrees C. Some of them were incorporated into the hydrophobic domain of recombinant human serum albumin (rHSA), providing albumin-heme hybrids (rHSA-heme), which can bind and release O2 in aqueous media (pH 7.3, 25 degrees C). The oxidation process of converting the dioxygenated heme in rHSA to the inactive Fe(III) state obeyed first-order kinetics, indicating that the mu-oxo dimer formation was prevented by the immobilization of heme in the albumin scaffold. The rHSA-heme, in which the histidylglycil tail coordinates to the Fe(II) center, showed the most stable O2 adduct complexes.  相似文献   

19.
Synthesis of Boryl-coupled Cyclotri- and -tetrasilazanes and four-membered Cycloborasilazanes – Thermal Decomposition to SiC and BN Dilithiated octamethylcyclotetrasilazane reacts with a difluoroboryl substituted cyclotrisilazane to give the BF coupled 6-8-6-membered cyclosilazane 1 , with Me2SiHCl structural isomeric cyclotetra- and cyclotrisilazanes of the type I and II, and with Me3SiCl structural isomeric cyclodisilazanes of the type III and IV are formed. The dilithium derivatives of the cyclosilazanes I and II as well as III and IV react with BF3 and a BF2-substituted cyclotrisilazane to give four-membered cyclo-borasilazanes which are coupled with a cyclodisilazane via a SiMe2-group ( 2 – 4 ). The six-membered cycloborasilazane 5 is a byproduct in the reaction with BF3. The reaction mechanisms are discussed. The pyrolysis with formation of SiC and BN and a crystal structure analysis were carried out with 1 .  相似文献   

20.
The reduction of (η-C5H5)2NbCl2 (I) under various conditions gives the dimer (η-C5H5)4Nb2Cl3 (II) containing niobium(III) and niobium(IV). Reaction of II with AgClO4 gives [(η-C5H5)4Nb2Cl2]+ ClO4- (III). FeCl3 and (C6F5)2 TlBr displace I from II to give (η-C5H5)2Nb(μ-Cl)(μ-X)MY2, where MFe, XYCl(IV) and MTl, XBr, YC6F5 (V). Reactions of I with metal halides MXY2 give (η-C5H5)2ClNb(μ-Cl)MXY2 where XYCl, MAl (VI), Fe (VII), Tl (VIII) and XBr, YC6F5, MTl (IX). The chemical behaviour of all these compounds is described.  相似文献   

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