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A structure involving the absolute configuration of acinetobactin (1b) was clarified. It was reconfirmed that preacinetobactin (1a) produced 1b by a rearrangement reaction. © 2010 Pharmaceutical Society of Japan.

DOI： 10.1248/cpb.58.1552

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Language：English   Publisher：GEORG THIEME VERLAG KG  

Intramolecular conjugate addition of gamma-substituted (E)-alpha,beta-unsaturated ketones with a Lewis acid (BF(3)center dot OEt(2)) Selectively afforded trans-2,3-disubstituted piperidine derivatives. Chiral substrates were synthesized by Sharpless asymmetric dihydroxylation of the enamine; the antimalarial compound febrifugine was synthesized from the major product of the conjugate addition reaction.

DOI： 10.1055/s-2008-1067271

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

In connection with studies on the total synthesis of toddaquinoline (1), the synthesis of [1,3]dioxolo[4',5':4,5]benzo[h]quinoline (1a), which is the tetracyclic core of 1, was investigated. Intramolecular benzene -pyridine coupling reactions of the monobromide (9) and dibromide (10), using a Pd reagent and Cu reagent, were evaluated to produce I a in poor to moderate yields.

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We examined palladium-assisted biaryl coupling reactions of 3-methoxy and 3-methoxycarbonyl benzanilidcs, and propose an aspect of the mechanism involved in forming a biaryl bond using Pd reagent.

DOI： 10.3987/COM-06-S(W)10

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

o-Nitrophenols and o-nitroanilme were reacted with amines at 210-215degreesC to produce the corresponding benzoxazoles and benzimidazoles, respectively, in moderate yields. The reactions between o-nitrophenols containing a CO2Me or OMe group on their benzene rings and N,N-diethylanitine were examined to investigate the effects of the position and electronic character of these substituents on the formation of the oxazole ring.

DOI： 10.3987/COM-04-S(P)11

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Intramolecular Pd-catalyzed coupling reactions of N-aryl-2-triflyloxybenzamides were examined. The procedure using DBU as a base was effective for even in the reaction of oxygen-substituted benzamides.

DOI： 10.3987/COM-04-S(P)7

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The biaryl coupling reaction of 1-benzoyl-7-iododihydroindole derivatives using Pd reagent was examined. 1-[(1,3-Benzodioxol-5-yl)carbonyl]-7-iodo-2,3-dihydroindole gave 4,5-dihydro-7H-[1,3]dioxolo[4,5-k]pyrrolo[3,2,1-de]phenanthridin-7-one, which was formed by connection to a more hindered carbon, as a major product. 1-(3,4-Dimethoxybenzoyl)-7-iodo-2,3-dihydroindole gave oxoassoanine and 10,11-dimethoxy-4,5-dihydropyrrolo[3,2,1-de]phenanthridin-7-one in an almost equal ratio.

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Heck reaction of N-(2-halophenyl)-N-methyl-1-cyclohexene-1-carboxamide (1) and 2-bromo-N-methyl-N-phenyl-1-cyclohexene-1-carboxamide (4) using a palladium reagent under several reaction conditions was examined. Reaction of 4 using Pd(OAc)(2), DPPP, and Bu3P afforded tetrahydrophenanthridone (5) in excellent yield.

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The stereo-structure of piperidine lactone (3), a synthetic intermediate of the antimalarial agent febrifugine ((+)-1) with a piperidine ring in the trans relative configuration, was re-revised to the cis-form. We determined that isomerization to the trans-form from the cis-form occurred in the stage (6 from 5) of deprotection in Baker's synthesis. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4020(03)00139-X

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The reaction of salicylaldehydes (2) with Horner-Wadsworth-Emmons (HWE) or Ando-HWE reagents was attempted to afford intramolecular phosphonate derivatives (6). A new synthetic method for coumarins (1) was achieved by using protected 2.

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The aryl-aryl coupling reaction of 2-triflyloxy-6-halobenzanilides using a palladium reagent under several reaction conditions was examined. The 6-iodo compound gave triflyloxyphenanthridone selectively in excellent yield under the conditions for the ordinary Heck reaction.

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Language：English   Publisher：PHARMACEUTICAL SOC JAPAN  

A palladium-assisted coupling reaction of aryl triflate with arene was investigated, and a novel Pd reagent prepared from equimolar Pd(OAc)(2), 1,3-Bis[diphenylphosphino]propane (DPPP), and BUY was developed. This method is useful for intramolecular biaryl coupling reactions, not only between aryl triflate and arene (triflate-amide), but also between aryl halide and arene (halo-amide).

DOI： 10.1248/cpb.50.519

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Language：English   Publisher：PHARMACEUTICAL SOC JAPAN  

The regioisomers (2a,b) of the piperidine ring of febrifugine (1a) and isofebrifugine (1b) were synthesized from 4-allyl-3-piperidone (5). Reduction of 5 afforded a mixture of the trans and cis alcohols (6a,b) without diastereoselectivity: this result differentiated it from the reduction of 2-allyl-3-piperidone (14), The antimalarial activity of 2a,b and related compounds was tested.

DOI： 10.1248/cpb.49.721

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Language：English   Publisher：PHARMACEUTICAL SOC JAPAN  

Total synthesis of vibrioferrin (1), a siderophore, was achieved via a chiral dibenzyl citrate obtained by optical resolution. The citrate moiety of vibrioferrin was determined to have the R configuration and one of the diastereomeric isomers (1b) of 1 did not exhibit siderophore activity.

DOI： 10.1248/cpb.47.1284

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Language：English   Publisher：PHARMACEUTICAL SOC JAPAN  

Total synthesis of vibrioferrin (1), a siderophore, was achieved via a chiral dibenzyl citrate obtained by optical resolution. The citrate moiety of vibrioferrin was determined to have the R configuration and one of the diastereomeric isomers (1b) of 1 did not exhibit siderophore activity.

DOI： 10.1248/cpb.47.1284

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Language：Japanese   Publisher：PHARMACEUTICAL SOC JAPAN  

The Baeyer-Villiger (B.V.) reaction using SeO2-H2O2 was examined for various benzaldehydes possessing methoxy groups and/or a furan ring. When benzaldehydes have an electron-donating group (methoxy group) at the ortho or para position to a formyl group, the B.V. reaction proceeded rapidly and in a good yield. Since the reaction using SeO2-H2O2 is carried out under a neutral condition, this reaction are applicable to aldehyde derivatives with a furan ring which is unstable against acid.

DOI： 10.1248/yakushi1947.119.7_519

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Language：Japanese   Publisher：PHARMACEUTICAL SOC JAPAN  

The Baeyer-Villiger (B.V.) reaction using SeO2-H2O2 was examined for various benzaldehydes possessing methoxy groups and/or a furan ring. When benzaldehydes have an electron-donating group (methoxy group) at the ortho or para position to a formyl group, the B.V. reaction proceeded rapidly and in a good yield. Since the reaction using SeO2-H2O2 is carried out under a neutral condition, this reaction are applicable to aldehyde derivatives with a furan ring which is unstable against acid.

DOI： 10.1248/yakushi1947.119.7_519

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Language：Japanese   Publisher：PHARMACEUTICAL SOC JAPAN  

The reaction of bromo-methoxysalicylaldehyde (4-6) and broma-hydroxysalicylaldehyde (18) with carbethoxymethylenetriphenylphosphorane (2) in diethylaniline under reflux gave unexpected debromocoumarins along with an expected bromocoumarin. The oxygen function might facilitate debromination in the process of coumarin synthesis at an elevated temperature.

DOI： 10.1248/yakushi1947.115.9_765

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Language：Japanese   Publisher：PHARMACEUTICAL SOC JAPAN  

The reaction of bromo-methoxysalicylaldehyde (4-6) and broma-hydroxysalicylaldehyde (18) with carbethoxymethylenetriphenylphosphorane (2) in diethylaniline under reflux gave unexpected debromocoumarins along with an expected bromocoumarin. The oxygen function might facilitate debromination in the process of coumarin synthesis at an elevated temperature.

DOI： 10.1248/yakushi1947.115.9_765

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Reaction of nitrosalicylaldehydes (1) with carbethoxymethylenetriphenylphosphorane in Et(2)NPh, in Ph(2)O, and in the absence of solvent (neat) at 210-215 degrees C was investigated. Reaction of 3-nitrosalicylaldehyde (1d) in Et(2)NPh afforded the benzoxazole (6) and the aminocoumarin (3e) along with the expected coumarin (3d). It was clarified that the origin of carbon-unit introduced for the formation of the benzoxazole ring came from the alkyl group of solvent.

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Reaction of nitrosalicylaldehydes (1) with carbethoxymethylenetriphenylphosphorane in Et(2)NPh, in Ph(2)O, and in the absence of solvent (neat) at 210-215 degrees C was investigated. Reaction of 3-nitrosalicylaldehyde (1d) in Et(2)NPh afforded the benzoxazole (6) and the aminocoumarin (3e) along with the expected coumarin (3d). It was clarified that the origin of carbon-unit introduced for the formation of the benzoxazole ring came from the alkyl group of solvent.

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：PHARMACEUTICAL SOC JAPAN  

Reaction of salicylaldehydes (1) with carbethoxymethylenetriphenylphosphorane in diethylaniline under reflux gave coumarins (3) in moderate to high yield except 3-methoxycarbonylsalicylaldehyde (1e) as summarized in Table I. The substituent effects are discussed. A substituent at C-6 on 1 usually facilitated the formation of the coumarin ring regardless of its electronic character.

DOI： 10.1248/cpb.42.2170

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：PHARMACEUTICAL SOC JAPAN  

Reaction of salicylaldehydes (1) with carbethoxymethylenetriphenylphosphorane in diethylaniline under reflux gave coumarins (3) in moderate to high yield except 3-methoxycarbonylsalicylaldehyde (1e) as summarized in Table I. The substituent effects are discussed. A substituent at C-6 on 1 usually facilitated the formation of the coumarin ring regardless of its electronic character.

DOI： 10.1248/cpb.42.2170

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Language：English   Publisher：PHARMACEUTICAL SOC JAPAN  

As part of a series of studies on synthesis of chiral 1-alkyltetrahydroisoquinolines, asymmetric synthesis of 1-alkoxycarbonylmethyl-1,2,3,4-tetrahydroisoquinoline (IV) was investigated. Two synthetic approaches using intermolecular and intramolecular Reformatsky-type reactions from (3R,10bS)-3-phenyl-2,3,5,6-tetrahydro-10bH-oxazolo[2,3-a]isoquinoline (1) were attempted, but high stereoselectivity could not be obtained. For the purpose of determining the absolute structures of the compounds (2, 3) obtained by the Reformatsky-type reactions, transformation of 3a to a chiral 1,3,4,6,7,11b-hexahydro-2H-benzo[a]quinolizine (14) was investigated.

DOI： 10.1248/cpb.42.796

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Language：English   Publisher：PHARMACEUTICAL SOC JAPAN  

As part of a series of studies on synthesis of chiral 1-alkyltetrahydroisoquinolines, asymmetric synthesis of 1-alkoxycarbonylmethyl-1,2,3,4-tetrahydroisoquinoline (IV) was investigated. Two synthetic approaches using intermolecular and intramolecular Reformatsky-type reactions from (3R,10bS)-3-phenyl-2,3,5,6-tetrahydro-10bH-oxazolo[2,3-a]isoquinoline (1) were attempted, but high stereoselectivity could not be obtained. For the purpose of determining the absolute structures of the compounds (2, 3) obtained by the Reformatsky-type reactions, transformation of 3a to a chiral 1,3,4,6,7,11b-hexahydro-2H-benzo[a]quinolizine (14) was investigated.

DOI： 10.1248/cpb.42.796

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：PHARMACEUTICAL SOC JAPAN  

A convenient and effective transformation of 2-methylbenzofuran (B) to salicylaldehyde (C) was achieved by ozonolysis of B in CH2Cl2 at -78-degrees-C followed by alkaline hydrolysis.

DOI： 10.1248/cpb.41.1166

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Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：PHARMACEUTICAL SOC JAPAN  

A convenient and effective transformation of 2-methylbenzofuran (B) to salicylaldehyde (C) was achieved by ozonolysis of B in CH2Cl2 at -78-degrees-C followed by alkaline hydrolysis.

DOI： 10.1248/cpb.41.1166

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