Shinya Harusawa

A novel synthesis of α,β-unsaturated nitriles from aromatic ketones via cyanophosphates

Abstract Reaction of aromatic ketones with diethyl phosphorocyanidate in the presence of lithium cyanide gave cyanophosphates, which were converted into α,β-unsaturated nitriles by treatment with boron trifluoride etherate in high yields.

An Efficient Synthesis of Magallanesine Using [1,2]-Meisenheimer Rearrangement and Heck Cyclization

Abstract A straightforward total synthesis of magallanesine 1 was accomplished from readily available isoquinolineacetate 14 . This synthesis is emphasized by the following two points; i. the [1,2]-Meisenheimer rearrangement of the azetidine N-oxide 22 for the preparation of azocine ring, ii. the Pd-catalyzed intramolecular Heck reaction of N-benzoylenaminone 38 for the construction of isoindoloazocine skeleton.

STEREOSELECTIVE SYNTHESIS OF THE C-4 LINKED IMIDAZOLE NUCLEOSIDES USING MODIFIED MITSUNOBU REACTION

Abstract A highly stereoselective synthesis of the novel 4-(β-D-ribofuranosyl)imidazole 5 was accomplished in 4 steps and 85% overall yield from protected D-ribose 1. Cyclization of the diol (RS)-3 having an intact imidazole by modified Mitsunobu reaction exclusively afforded benzylated β-ribofuranosylimidazole β-4a, accompanied by α-4a, in a ratio of 26:1. Reductive debenzylation completed the synthesis. 2′-Deoxy derivative 8 was also synthesized stereoselectively in the same manner.

Non-aqueous cyanation of halides using lithium cyanide

Abstract Efficient conversion of various halides into the corresponding nitriles with lithium cyanide in tetrahydrofuran is described.

Cyanophosphate: an efficient intermediate for conversion of carbonyl compounds to nitriles

Abstract A novel and high yield conversion of saturated or unsaturated carbonyl compounds to nitriles via cyanophosphates by samarium diiodide in the presence of tert -butanol is described.

Synthesis of imifuramine and its stereoisomers exhibiting histamine H3-agonistic activity

Abstract The four possible stereoisomers of a novel imidazole C-nucleoside derivative were synthesized by the efficient use of a PhSe group. Among them, (+)-4(5)-[(2R,5R)-5-(aminomethyl)tetrahydrofuran-2-yl]imidazole (imifuramine) was indicated as a novel type of histamine H 3 -agonist by a brain microdialysis method.

A total synthesis of magallanesine via [1,2]-Meisenheimer rearrangement

Abstract A straightforward synthesis of magallanesine 1 from azetoisoquinoline 4 has been accomplished via [1,2]-Meisenheimer rearrangement and an intramolecular Heck cyclization as the key reactions.

A New Synthesis of Some Non-Steroidal Anti-Inflammatory Agents via Cyanophosphates1)

Abstract A simple and convenient procedure for the syntheses of some nonsteroidal anti-inflammatory agents, ibuprofen, rac-naproxen, clidanac and loxoprofen, is described.

Synthesis of (Z)-predominant α,β-unsaturated nitriles from enone cyanohydrin diethyl phosphates: application to the synthesis of (±)-nuciferal, (±)-(E)- and -(Z)-nuciferol, and (±)-manicone

Enone cyanohydrin diethyl phosphates reacted regio- and stereo-selectively with a variety of organocopper reagents to give γ-coupling products, (Z)-predominant alk-2-enenitriles. The methodology was applied to the synthesis of (±)-nuciferal, (±)-(E)- and -(Z)-nuciferol, and (±)-manicone.

A New Synthesis of Polysubstituted Cyclopropanes

Abstract Polysubstituted cyclopropane derivatives (3a-3h) could be obtained by reaction of activate olefinic compounds (2) with the cyanophosphates (1) aldehydes (benzaldehyde, cinnamaldehyde and croton-aldehyde) in the presence of butyllithium and tetra-methylethylenediamine in tetrahydrofuran via a Michael addition followed by 1,3-elimination.