Nucleophilic Addition of Amides to Haloalkynes: Synthesis of ()-β-Halovinyl Amides as Dual Precursors of Alkylidene Carbenes and Allyl Halides.

Toward a regioselective method for the synthesis of β-halovinyl amides, we developed a transition-metal-free nucleophilic addition reaction of amides to haloalkynes. The regioselective nucleophilic addition was achieved under solvent-free conditions using phosphonates to protonate the intermediate alkylidene carbenoids, thus suppressing their decomposition. Furthermore, we demonstrate that β-halovinyl amides can serve as dual precursors of allyl halides and alkylidene carbenes to obtain functionalized indoles and pyrrolidones.

Facile preparation of polycyclic halogen-substituted 1,2,3-triazoles by using intramolecular Huisgen cycloaddition.

When 1-(ω-azidoalkyl)-2-(2,2-dihalovinyl)arenes were heated in DMF, the intramolecular Huisgen cycloaddition of an azido group with a 1,1-dihalovinyl group afforded 5-halo-1,2,3-triazole-fused tricyclic benzo compounds. Based on the remaining bromo groups, carbon elongation by the Mizoroki-Heck or Suzuki-Miyaura coupling reactions, followed by an intramolecular Friedel-Crafts reaction, afforded polycyclic compounds with fused triazole rings. Thereafter, the bromo groups were converted into 2-nitrophenyl groups the Suzuki-Miyaura coupling reaction, which was followed by the Cadogan reaction; a fluorescent pentacyclic compound was obtained.

A mutation in the Cc.arp9 gene encoding a putative actin-related protein causes defects in fruiting initiation and asexual development in the agaricomycete Coprinopsis cinerea.

Agaricomycetes exhibit a remarkable morphological differentiation from vegetative mycelia to huge fruiting bodies. To investigate the molecular mechanism underlying the fruiting body development, we have isolated and characterized many Coprinopsis cinerea mutant strains defective in fruiting initiation to date. Dikaryon formation in agaricomycetes, which is followed by fruiting development, is governed by the mating type loci, A and B.

Rhodium-Catalyzed Intramolecular C-H Bond Activation with Triazoles: Preparation of Stereodefined Pyrrolidines and Other Related Cyclic Compounds.

On treatment of triazoles having an N-sulfonyl-protected benzylamine moiety with [Rh2 (C7 H15 CO2 )4 ], intramolecular C-H bond insertion takes place at the benzylic position to give cis-N-sulfonyl-2-aryl-3-[(sulfonylimino)methyl]pyrrolidines in good yields and with highly stereoselectivities. Analogously, the similar treatment of triazoles having an ether or even an alkyl moiety affords 2-alkyl- or 2-aryl-3-[(sulfonylimino)methyl]tetrahydrofurans or a 2-alkyl-3-[(sulfonylimino)methyl]cyclopentane in good yields.

Alkylation of pyridines at their 4-positions with styrenes plus yttrium reagent or benzyl Grignard reagents.

A new regioselective alkylation of pyridines at their 4-position was achieved with styrenes in the presence of yttrium trichloride, BuLi, and diisobutylaluminium hydride (DIBAL-H) in THF. Alternatively, similar products were more simply prepared from pyridines and benzyl Grignard reagents. These reactions are not only a useful preparation of 4-substituted pyridines but are also complementary to other relevant reactions usually giving 2-substituted pyridines.

Rhodium-catalyzed intramolecular hydroarylation of 1-halo-1-alkynes: regioselective synthesis of semihydrogenated aromatic heterocycles.

The regioselective intramolecular hydroarylation of (3-halo-2-propynyl)anilines, (3-halo-2-propynyl) aryl ethers, or (4-halo-3-butynyl) aryl ethers was efficiently catalyzed by Rh2(OCOCF3)4 to give semihydrogenated aromatic heterocycles, such as 4-halo-1,2-dihydroquinolines, 4-halo-3-chromenes, or 4-(halomethylene)chromans, in good to excellent yields. Some synthetic applications taking advantage of the halo-substituents of the products are also illustrated.

Facile preparation of indoles and 1,2-benzothiazine 1,1-dioxides: nucleophilic addition of sulfonamides to bromoacetylenes and subsequent palladium-catalyzed cyclization.

Bromine as a double agent: The bromine atom in 1-bromo-1-alkynes works as an electron-withdrawing group to effect the nucleophilic addition of sulfonamides. It again plays a pivotal role in the palladium-catalyzed cyclization of the resultant (Z)-2-(sulfonylamino)-1-bromoalkenes into nitrogen heterocycles (see scheme).

Four nucleophilic additions to alkenynedioic acid derivatives in tandem; efficient one-pot synthesis of bicyclo[4.2.0]octenols.

When alkenynedioic acid derivatives were treated with a Grignard reagent, tandem cyclization and the incorporation of two molecules of the Grignard reagent occurred to give stereodefined bicyclo[4.2.0]octenols via four nucleophilic additions.

Acute coronary occlusion by injured aortic valve during percutaneous coronary intervention.

We report a rare case of a 58-year-old male with accidental occlusion of left main trunk (LMT) artery by injured aortic valve during percutaneous coronary intervention (PCI). Although we successfully bailed out this complication by urgent LMT stenting, aortic regurgitation developed immediately after PCI. Echocardiography detected a filamentous structure attached to the aortic valve.

Additive-free nucleophilic addition of imidazolines and imidazoles to haloacetylenes.

Nucleophilic addition of imidazolines to 1-halo-1-alkynes takes place by simple heating in DMF without any additives to give (Z)-N-(1-halo-1-alken-2-yl)imidazolines in good yield and in a highly regio- and stereoselective manner. These reaction conditions are also valid for the similar addition of imidazoles.

Iron-mediated and -catalyzed metalative cyclization of electron-withdrawing-group-substituted alkynes and alkenes with Grignard reagents.

Treatment of ethyl (E)-5,5-bis[(benzyloxy)methyl]-8-(N,N-diethylcarbamoyl)-2-octen-7-ynoate with an iron reagent generated from FeCl(2) and tBuMgCl in a ratio of 1:4 (abbreviated as FeCl(2)/4 tBuMgCl) afforded ethyl [4,4-bis[(benzyloxy)methyl]-2-[(E)-(N,N-diethylcarbamoyl)methylene]cyclopent-1-yl]acetate in good yield. Deuteriolysis of an identical reaction mixture afforded the bis-deuterated product ethyl [4,4-bis[(benzyloxy)methyl]-2-[(E)-(N,N-diethylcarbamoyl)deuteriomethylene]cyclopent-1-yl]deuterioacetate, thus confirming the existence of the corresponding dimetalated intermediate. The latter intermediate can react with halogens or aldehydes to facilitate further synthetic transformations.

Nucleophilic addition of sulfonamides to bromoacetylenes: facile preparation of pyrroles.

Nucleophilic addition of sulfonamides to 1-bromo-1-alkynes provided (Z)-N-(1-bromo-1-alken-2-yl)-p-toluenesulfonamides in good yield and in a highly regio- and stereoselective manner. Treatment of product (Z)-N-(1-bromo-1-octen-2-yl)-N-allyl-p-toluenesulfonamide with a palladium catalyst under Heck conditions afforded 1-(p-toluenesulfonyl)-2-hexyl-4-methylpyrrole in good yield. Other pyrroles with various substituents can also be prepared in good yield by this method.

Mutation analysis of 2009 pandemic influenza A(H1N1) viruses collected in Japan during the peak phase of the pandemic.

Background: Pandemic influenza A(H1N1) virus infection quickly circulated worldwide in 2009. In Japan, the first case was reported in May 2009, one month after its outbreak in Mexico. Thereafter, A(H1N1) infection spread widely throughout the country.

Aryl(sulfonyl)amino group: a convenient and stable yet activated modification of amino group for its intramolecular displacement.

Aryl(sulfonyl)amino groups, readily derived from sulfonyl- or arylamines by standard methods as well as the recently introduced methods of sulfonylation and arylation, proved to be good leaving groups in intramolecular substitution reactions by various nitrogen, oxygen, and carbon nucleophiles.

Selective deprotection of methanesulfonamides to amines.

Methanesulfonamides were deprotected to their parent amines via deprotonation and oxygenation with O(2) (g), even in the presence of other traditional sulfonamides.

Iron-catalyzed regio- and stereoselective substitution of gamma,delta-epoxy-alpha,beta-unsaturated esters and amides with Grignard reagents.

When gamma,delta-epoxy-alpha,beta-unsaturated esters or amides were treated with 2 equiv of Grignard reagents in the presence of 10-24 mol % FeCl(2), regio- and stereoselective substitution of the epoxide moiety with the Grignard reagent occurred to give exclusively delta-hydroxy-gamma-alkyl or aryl-alpha,beta-unsaturated esters or amides in good yields.

Rh-catalyzed isomerization and intramolecular redox reaction of alkynyl ethers affording dihydropyrans and ketoolefins.

When arylmethyl 4-(sulfonyl)-3-butynyl ether and a catalytic amount of Rh(2)(tfa)(4) (tfa = CF(3)CO(2)-) were heated in toluene, 2-aryl-3-(sulfonyl)-5,6-dihydro-2H-pyran was produced in good yield. Ring closure proceeded in a highly regioselective manner, and no isomeric five-membered product was detected. Alternatively, 2-(5-sulfonyl-4-pentynyl)tetrahydrofuran lacking a benzyl substituent afforded a different product, 9-sulfonyl-1-hydroxy-8-nonen-4-one, upon reaction with the same rhodium catalyst at reflux in wet toluene.

Iron-mediated intramolecular metalative cyclization of alpha,beta-unsaturated esters and amides. Versatile one-pot preparation of bicyclic ketoesters.

2-Nonen-7-ynedioic or 2-decen-8-ynedioic acid derivatives were treated with an iron reagent generated from FeCl2 and t-BuMgCl in a ratio of 1:4 to give cyclized products after hydrolysis, deuteriolysis, or the addition of carbonyl compounds. Upon reaction with the same iron reagent, 2,7-nonadienedioates afforded bicyclic ketoesters (and their enol forms) after the addition of s-BuOH or carbonyl compounds.

Transient enhancement of oxidant stress and collagen turnover in patients with acute worsening of congestive heart failure.

Background: Myocardial remodeling is a crucial step for progression of heart failure (HF). Free radical generation by the failing myocardium has been proposed as linked to myocardial remodeling. The aim of this study was to evaluate the urinary excretion of 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha), a reliable marker for oxidant stress in vivo, and collagen turnover in patients with acute worsening of congestive HF.

Hereditary protein s deficiency with a history of recurrent myocardial infarction.

Protein S is a vitamin K-dependent plasma protein that inhibits the process of blood coagulation via activation of protein C, another vitamin K-dependent plasma protein A 58-year-old man with hereditary protein S deficiency had repeated attacks of acute myocardial infarction at age 52 and 58 years.

Asymmetric synthesis of axially chiral benzamides and anilides by enantiotopic lithiation of prochiral arene chromium complexes.

Axially chiral benzamides and anilides were prepared by enantiotopic lithiation at the distinguished benzylic methyl of prochiral tricarbonylchromium complexes of N,N-diethyl 2,6-dimethylbenzamide (1) and N-methyl-N-acyl 2,6-dimethylaniline (14 and 21) with a chiral lithium amide base followed by electrophilic substitution in good yields with high optical purity. The resulting axially chiral chromium-complexed benzamides and anilides were oxidized under air to give chromium-free axially chiral benzamides and anilides in an enantiomerically active form without axial bond rotation at room temperature.