Preparation of the isomeric azaindoline family by intramolecular carbolithiation

An operationally convenient, one-pot, three-step sequence has been developed that provides access to 3-substituted 4-, 5-, 6-, and 7-azaindolines (2,3-dihydro-1H-pyrollopyridines) via intramolecular carbolithiation of the aryllithium derived from an appropriate (N,N-diallylamino)bromopyridine. Whereas cyclization proceeds as expected to give 1-allyl-3-methyl-4-azaindoline and 1-allyl-3-methyl-6-azaindoline following protonation of the 3-CH2Li group of the azaindoline, the isomeric 3-methyl-5-azaindoline and 3-methyl-7-azaindoline are generated as 3-methyl-N-allyl anions prior to quench with MeOH.     

Synthesis of 6-arylazo-substituted 5-hydroxy-2-hydroxymethyl-4-pyridones and related compounds

5-Hydroxy-2-hydroxymethyl-4-pyridone ( 1 ) and 5-hydroxy-2-hydroxymethyl-1-methyl-4-pyridone ( 2 ) reacted with arenediazonium salts to give 6-arylazo-substituted compounds 3a-d and 4a-d , respectively. Compounds 3a-d were methylated with diazomethane to afford 6-arylazo-2-hydroxymethyl-4,5-dimethoxypyridines 5a-d .     

Cyclic acylimines and cyclic carbinolamides III. Piperidone and isoindolone

6-Phenyl-2,3,4,5-tetrahydro-3,3,5,5-tetramethyl-2-pyridone ( 6 ), 1-phenyl-3-isoindolone, and their methanol ( 5 ) and butanol ( 19 ) addition products, as well as 6-methoxy-3,3,5,5-tetramethyl-2-piperidone ( 4 ) and 1-methoxy-3-isoindolinone ( 11 ) were prepared and their chemical properties studied. The cyclic acylimines and their methanol addition products were found to react with weak nucleophiles (amides, alcohols), active methylene compounds (acetone, dimedone) or dienes (1,2,3,4-tetramethyl and 2,3-dimethylbutadiene) to give addition products.     

4-烯丙氧基吡啶-1-氧化物的合成及其重排反应的研究

在烯丙醇中用4-氯吡啶-1-氧化物与烯丙醇钠于温和的条件下作用,以很好的收率合成出4-烯丙氧基吡啶-1-氧化物,并在真空中研究了它的热重排。我们发现:除生成正常的克莱森重排产物3-烯丙基-4-羟基吡啶-1-氧化物外,另一重排产物是N-烯丙基-4-吡啶酮。     

Reaction of 2,6-dibutylaminohepta-2,5-dien-4-one with malononitrile

Malononitrile reacted with the title compound to give 6-amino-5-cyano-2-(3,3-dicyano-2-methylallylidene-4-methyl-2H-pyran (3). Treatment of 3 with hot 80% sulfuric acid yielded 4,7-dimethyl-56-hydroxy-2(1H)quinolone. With concentrated aqueous sodium hydroxide, 3 gave 5-amino-3,6-dicyano-4,7-dimethyl-2(1H)quinolone and 5-amino-6-carbamoyl-3-cyano-4,7-dimethyl-2(1H)quinolone. The reaction of 3 with hydrochloric in acetic acid gave a mixture of 6-amino-3,7-dicyano-2,8-dimethyl-4-quinolizone and 3-cyano-4-methyl-6-(3,3-dicyano-2-methylallyl)-2-pyrone. Compound 3 also reacted with methylamine, butylamine and piperidine to give 8-amino-5-cyano-4-methyl-2-pyridone, 6-bulylamino-5-cyano-4-methyl-2-pyridone and 5-eyano-4-methyl-6-piperidino-2-pyridone respectively.     

Stereoselective synthesis of c3-c12 dihydropyran portion of antitumor laulimalide using copper-catalyzed oxonium ylide formation-[2,3] shift

Copper-catalyzed oxonium ylide formation-[2,3] shift of (5S,7R)-5-allyloxy-1-diazo-8-(p-methoxybenzyloxy)-7-methyl-2-octanone (3) proceeded in tetrahydrofuran-dichloromethane (4 : 1) under reflux with an excellent stereoselectivity (97 : 3) to give (2R,6S)-2-allyl-6-[(2R)-3-(p-methoxybenzyloxy)-2-methylpropyl]-3-dihydropyranone (2) as a major isomer in 82% yield. The resultant pyranone (2) was converted to the key intermediate (1) of the Mulzer's laulimalide synthesis and its derivatives (14, 15).     

Alkylation of 3-cyano-4-methoxymethyl-6-methyl-2(1h)-pyridone by active halomethylene compounds. The molecular structure of 3-amino-2-benzoyl-4-methoxymethyl-6-methylfuro[2,3-<Emphasis Type="Italic">b</Emphasis>]pyridine

The alkylation of 3-cyano-4-methoxymethyl-6-methyl-2(1H)-pyridone by active halomethylene compounds has been studied. It was shown that the reaction of the pyridone with methyl- and ethylchloroacetates and phenacyl and p-bromophenacyl bromides occurs to give N- and O-structural isomers. Only the N-derivatives are separated from the reaction mixture when the pyridone is alkylated with iodoacetamide. It was found that 2-aroylmethyl-3-cyano-4-methoxymethyl-6-methylpyridines cyclize in the presence of KOH to 3-amino-2-aroyl-4-methoxymethyl-6-methylfuro[2,3-b]pyridines. The molecular structure of 3-amino-2-benzoyl-4-methoxymethyl-6-methylfuro[2,3-b]pyridine has been studied using an X-ray analytical method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1670–1682, November, 2004.     

4(3H)-Quinazolinones containing heterocyclic group in position 3

The corresponding 2,3-substituted 4(3H)-quinazolinones were obtained in the reactions of 2-methyl- and 2-phenyl-4-oxo-3,1-benzoxazines with 1-amino-1,2,4-triazole, 4-amino-2,3-dimethyl-1-phenyl-5-pyrazolone, 2-amino-5-ethyl-1,3,4-thiadiazole, 3-amino-6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazole, 1-amino-3-cyano-4,6-dimethyl-2-pyridone, and 1-amino-3-cyano-6-phenyl-4-trifluoromethyl-2-pyridone. The formation of N-benzolyanthranilamides in the reactions of 2-phenyl-4-oxo-3,1-benzoxazine with 2-amino-5-ethyl-1,3,4-thiadiazole and 1-amino-3-cyano-6-phenyl-4-trifluoromethyl-2-pyridones was exceptional. The structures of two of the products have been confirmed by X-ray crystallography.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 936–943, July, 2000.     

Synthesis of diversely functionalized hexahydropyrrolo[2,3-b]indoles using domino reactions, olefination, isomerization and Claisen rearrangement followed by reductive cyclization

Hexahydropyrrolo[2,3-b]indoles 6 were synthesized in five steps from indolin-3-one 8 by a general and efficient method, in which elements of molecular diversity were readily added onto the 3a-position of the pyrrolo[2,3-b]indole ring system. Horner-Wadsworth-Emmons reaction of 2-allyloxyindolin-3-ones 7, derived from indolin-3-one 8 and a variety of allylic alcohols, smoothly proceeded with successive Claisen rearrangement to give the corresponding 3-allyl-3-cyanomethylindolin-2-ones 15. Indolin-2-ones 15 were converted into pyrrolo[2,3-b]indoles 6 using partial hydrolysis followed by reductive cyclization with LiAlH(4). Synthesis of N-methylated pyrrolo[2,3-b]indole derivatives 23 and 26 is also described.     

Isolierung von 1-Allyl-2, 3-dimethoxy-4, 5-methylendioxybenzol (= Dill-Apiol)aus Heckeria umbellata (L.) Kunth (Piperaceae)

Isolation of 1-Allyl-2,3-dimethoxy-4,5-methylenedioxybenzene from Heckeria umbellata (L. ) KUNTH (Piperaceae) From the leaves of Heckeria umbellata (L.) KUNTH an oily substance was isolated and its structure deduced. It is 1-allyl-2, 3-dimethoxy-4, 5-methylenedioxybenzene (= Dill-Apiol; 2 ) and not as previously published 1-allyl-2, 5-dimethoxy-3, 4-methylenedioxybenzene (= Apiol; 1 ) [2].     

Säurekatalysierte Dienon-Phenol-Umlagerungen von Allylcyclohexadienonen; ladungsinduzierte und ladungskontrollierte sigmatropische Reaktionen

The rearrangement of 10-allyl-2-oxo-Δ^{1(9), 3}-hexahydronaphthalene ( 12 ) catalysed by trifluoroacetic acid and other Bronsted acids yielded almost exclusively the [3s, 3s]-products, 1- and 3-allyl-5,6,7,8-tetrahydro-2-naphthol ( 16 and 15 , respectively). The rearrangement of 12 with trifluoroacetic anhydride or acetic anhydride/sulfuric acid, yields, besides 15 and 16 , appreciable amounts of the [1s, 2s]-rearrangement product, 4-allyl-5,6,7,8-tetrahydro-2-naphthol ( 14 ) (table 1). The CF₃COOH catalysed dienone-phenol-rearrangement of 6-ally-5,6-dimethyl-cyclohexa-2,4-dien-l-one ( 11 ) in hexane at 0° yields4-allyl-2,3-dimethyl-phenol ( 19 ). Rearrangement of d₃- ll containing a specifically deuteriated allyl group proves that the formation of d₃- 19 occurs via a [3s, 3s]-sigmatropic reaction. On the other hand, treatment of 11 with (CF₃CO)₂O at 0° in hexane gives (after saponification) 4-allyl-, 5-allyl- and 6-allyl-2,3-dimethyl-phenol ( 19 , 20 and 21 , respectivcly). This reaction occurs via an acyloxybenzenium-ion intermediate. The reactions performed with d₃- 11 demonstrate that the formation of d₃- 19 occurs both by a direct [3s, 3s]-shift and by a twofold [1s, 2s]-shift, respectively. d₃- 20 is formcd by a [3s, 4s]-sigmatropic reaction. d₃- 21 is obtained with about 95% inversion of the carbon skeleton of the allyl group. Thus d₃- 21 is mainly formed by a [1s, 2s]- followed by a [3s, 4s]-sigmatropic rearrangement. 6-Allyl-6-niethyl-cyclohexa-2,4-dien-1-one ( 4 ) yields with CF₃COOH in hexane 4-allyl-2-methyl-phenol ( 5 ), whereas with (CF₃CO)₂O in hexane 5 , 3-allyl- and 5-allyl-2-methyl-phenol ( 24 and 25 , respectively) are formed in comparable amounts. As a minor product 6-allyl-2-methyl-phenol ( 26 ) was observed. Based on these observations, the concept of charge-induced, e.g. schemes 2 and 3, and charge-controlled, e.g. scheme 7, sigmatropic reactions, has been elaborated. In the former, the charge serves only to accelerate appreciably thermal orbital-symmetry allowed reactions, whereas in the latter, the charge determines the course of the transformations according to the Woodward-Hoffmann rules. Especially in acetylating systems, allylcyclohexdienones undergo charge-induced and charge-controlled reactions simultaneously.     

The synthesis of 3-deazapyrimidine nucleosides related to uridine and cytidine and their derivatives

Condensation of 2,4-bis(trimethylsilyloxy)pyridine ( 1 ) with 2,3,5-tri-O-benzoyl-D-ribofuranosyl bromide ( 2 ) gave 4-hydroxy-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-2-pyridone ( 3 ). Deblocking of 3 gave 4-hydroxy-1-β-D-ribofuranosyl-2-pyridone (3′-deazauridine) ( 4 ). Treatment of 4 with acetone and acid gave 2′,3′-O-isopropylidene-3-deazauridine ( 6 ). Reaction of 4 with diphenylcarbonate gave 2-hydroxy-1-β-D-arabinofuranosyl-4-pyridone-O₂←2′-cyclonucleoside ( 7 ) which established the point of gylcosidation and configuration of 4 . Base-catalyzed hydrolysis of 7 gave 4-hydroxy-1-β-D-arabinofuranosyl-2-pyridone (3-deazauracil arabinoside) ( 12 ). Fusion of 1 with 3,5-di-O-p-toluyl-2-deoxy-D-erythro-pentofuranosyl chloride ( 5 ) gave the blocked anomeric deoxynucleosides 8 and 10 which were saponified to give 4-hydroxy-1-(2-deoxy-β-D-erythro-pentofuranosyl)-2-pyridone (2′-deoxy-3-deazauridine) ( 11 ) and its α anomer ( 9 ). Condensation of 4-acetamido-2-methoxypridine ( 13 ) with 2 gave 4-acetamido-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-2-pyridone ( 14 ) which was treated with alcoholic ammonia to yield 4-acetamido-1-β-D-ribofuranosyl-2-pyridone ( 15 ) or with methanolic sodium methoxide to yield 4-amino-1-β-D-ribofuranosyl-2-pyridone (3-deazacytidine) ( 16 ). Condensation of 13 and 2,3,5-tri-O-benzyl-D-arabinofuranosyl chloride ( 17 ) gave the blocked nucleoside 22 which was treated with base and then hydrogenolyzed to give 4-amino-1-β-D-arabinofuranosyl-2-pyridone (3-deazacytosine arabinoside) ( 23 ). Fusion of 13 with 5 gave the blocked anomeric deoxynucleosides 18 and 20 which were deblocked with methanolic sodium methoxide to yield 4-amino-1-(2-deoxy-β-D-erythro-pentofuranosyl)-2-pyridone (2′-deoxy-3-deazacytidine) ( 21 ) and its a anomer 19 . The 2′-deoxy-erythro-pentofuranosides of both 3-deazauracil and 3-deazacytosine failed to obey Hudson's isorotation rule but did follow the “quartet”-“triplet” anomeric proton splitting pattern in the ¹H nmr spectra.     

Thermische umlagerungen-XV. Die thermische isomerisierung von 1,9-decadien-5-in und 6-hepten-2-in-1-ylacetat

Two novel thermal rearrangements providing 2,3-disubstituted 1,3-butadienes are described: the isomerization of 1,9-decadien-5-yne (3) to 4,5-bismethylene-1,7-octadiene (5) and of 1-acetoxy-6-hepten-2-yne (10) to 2-acetoxy-3-allyl-1,3-butadiene (12).     

A versatile and efficient synthesis of (2S)-2-(hydroxymethyl)-N-Boc-2,3-dihydro-4-pyridone

A versatile and efficient method for the preparation of (2S)-2-(hydroxymethyl)-N-Boc-2,3-dihydro-4-pyridone from l-(−)-phenylalanine 2 utilising the aromatic system as a masked β-keto aldehyde was developed. The key step in the sequence is an intramolecular cyclisation of 6 to give 2,3-dihydropyridin-4-ones.     

Investigation of structural and biological properties of N-heterocyclic carbene silver(I) and palladium(II) complexes

abstract

Computational investigations were done on bis(1-allyl-3-benzyl-2,3-dihydro-1H-benzo[d]imidazol-2-yl)silver(I), bis(1-benzyl-3-butyl-2,3-dihydro-1H-benzo[d]imidazol-2-yl)silver(I), bis(1-allyl-3-benzyl-2,3-dihydro-1H-benzo[d]imidazol-2-yl)dibromidepalladium(II), and bis(1-benzyl-3-butyl-2,3-dihydro-1H-benzo[d]imidazol-2-yl)dibromidepalladium(II) complexes. Related complexes were optimized at different six calculation levels which are HF/6-31G(LANL2DZ), HF/6-31G(d,p)(LANL2DZ), B3LYP/6-31G(LANL2DZ), B3LYP/6-31G(d,p)(LANL2DZ), M062X/6-31G(LANL2DZ) and M062X/6-31G(d,p)(LANL2DZ) levels in vacuo. IR and NMR spectrum are calculated and examined in detail. Energy diagram of molecular orbitals, contour diagram of frontier molecular orbitals, molecular electrostatic potential maps and the harmonic surface of related molecules are examined in detail. Finally, interactions between mentioned complexes and related proteins (1BNA, 1JNX, and 2ING) are investigated in detail. As a result, it is found that biological and anti-cancer properties of silver N-heterocyclic carbene complexes are higher than those of palladium complexes.     

Features of reaction of aromatic nitro-substituted aldehydes with ketones on the matrix of 2(1<Emphasis Type="Italic">H</Emphasis>)-pyridone

Condensation of nitrobenzaldehydes with 3-acetyl-4,6-dimethyl-2(1H)-pyridone gives rise to chalcones with high yield. Condensation of the close analogs of 3-acetyl-4,6-dimethyl-2(1H)-pyridone containing ethyl and benzyl radical was established to give stable products of aldol condensation, the corresponding alcohols, under the same conditions.     

Reactions of (Me2N)3P with functionalized di- and trichlorocyclopentenones

2,3-Dichloro-4,4-ethylenedioxycyclopent-2-enone, its 5-chloroderivative, and 5-allyl-2,3,5-trichloro-4,4-dimethoxycyclopent-2-enone react with (Me₂N)₃P to give the corresponding products of substitution of the NMe₂ group for the vinylic Cl atom at C(3). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2555–2556, December, 1998.     

An efficient synthesis of the anti-asthmatic agent T-440: a selective N-alkylation of 2-pyridone

6,7-Diethoxy-1-[1-(2-methoxyethyl)-2-oxo-1,2-dihydropyridin- 4-yl]naphthalene-2,3-dimethanol [T-440, (1)] is a potential anti-asthmatic agent based on selective phosphodiesterase 4 inhibition. It was necessary for the further evaluation of 1 to develop an efficient synthetic route for 1, especially the construction of the 1-(2-methoxyethyl)-2-pyridone moiety. We examined an N-selective alkylation of pyridone derivative (2) in basic media. 2-Methoxyethylation of 2 with 2-methoxyethyl iodide utilizing LiH as the base gave predominantly an N-alkyl pyridone derivative (3a) in 82% yield (N/O-alkylation=92/8), which is compatible with an ab initio calculation of transition-state structures for the methylation of 2-pyridone. Single crystallization of a crude mixture of 3a and 4a furnished pure 3a, which is a key synthetic intermediate of 1.     

The synthesis of 3-deazaorotidine and related nucleoside derivatives of 4-hydroxy-2-pyridone

Condensation of 6-earbethoxy-4-hydroxy-2-pyridone or a silyl derivative of 5-earbomethoxy-4-hydroxy-2-pyridone with 2′,3′,5′-tri-O-benzoyl-D-ribofuranosyl halide has provided the 3-deaza analogs of orotidine and uridine-5-carboxylic acid. The corresponding amides have also been prepared in view of their possible structural relationship to l-β-D-ribohiranosyl nicotinamide. Tri-O-benzoyl-3-deazauridine was treated with N-bromosuccinimide to give, after deblocking, 3-bromo-4-hydroxy-1-(β-D-ribofuranosyl)-2-pyridone. The anomeric configuration of these nuclcosides was confirmed by pmr spectroscopy.     

Photochemistry of 4-Thia-2-cycloalkenones. Part 2

Methyl 2-allyl-3-oxo-2,3-dihydrothiophene-2-carboxylate ( 2 ) photocyclizes selectively to methyl 2-oxo-7-thiatricyclo[3.2.1.0^3,6]octane-1-carboxylate ( 4 ). In contrast, 4-thia-2-cyclohexenone 3 , on irradiation, affords only low yields of dimers, cycloadducts (2-methylpropene) or RH reduction products (i-ProH).