Synthesis of 1-(α-phenylethyl)azetidin-2-ones

Phase-transfer catalyzed cyclization of racemic and optically active N-substituted -aminoacids has given racemic and optically active 2-azetidinones, the spatial structures of which have been established by NMR spectroscopy. The original -aminoacids were obtained by adding -phenylethylamine to substituted acrylic acids.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1644–1647, December, 1984.     

Some reactions of 1-methyl-(2-phenylethyl)-1,2,3,4-tetrahydropyridines with organic azides. Synthesis of 1-methyl-(2-phenylethyl)piperidylidene-2-sulfonamides

The 1,3-dipolar cycloaddition reaction of 1-methyl- and 1-(2-phenylethyl)-1,2,3,4-tetrahydropyridines 7 with organic azides 8 afforded the respective 1-substituted-piperidylidene-2-sulfon(cyan)amides 9. Nitration of the 1-(2-phenylethyl) analogue 9o yielded the 1-[2-(4-nitrophenyl)ethyl] derivative 9r which on reduction with palladium-on-charcoal and hydrazine gave the 1-[2-(4-aminophenyl)ethyl] analogue 9s.     

Six new 2-(2-phenylethyl)chromones from Agarwood

Six new chromones, 6-methoxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyllchromone (2), 6,8-dihydroxy-2-(2-phenylethyl)chromone (3), 6-hydroxy-2-[2-(4-hydroxyphenyl)ethyl]chromone (4), 6-hydroxy-2-[2-(2-hydroxyphenyl)ethyl]chromone (5), 7-hydroxy-2-(2-phenylethyl)chromone (6), and 6-hydroxy-7-methoxy-2-(2-phenylethyl)chromone (7) were isolated from the ether extract of agarwood in addition to a known compound, 2-(2-phenylethyl)chromone or flidersiachromone (1). Their structures were determined by spectroscopic methods including UV, IR, and NMR spectral data and comparisons with the calculated values using the hydroxyl and methoxyl substituent increments of the chromone ring.     

Efficient preparation of (1′R)-(−)-1-(2′-hydroxy-1′-phenylethyl)piperidin-2-one: synthesis of (2′S,3R)-(+)-stenusine

An efficient oxidation of (2′R)-(−)-2′-phenyl-2′-(piperidin-1-yl)ethanol 2 with bromine to generate the corresponding piperidin-2-one 3 in 96% is described. In addition, starting from 3, (2′S,3R)-(+)-stenusine 8 was synthesized in 70% overall yield. The X-ray analysis of piperidine 6·HCl is also reported.     

Facile Synthesis of 5-Hydroxy-2-（2-phenylethyl）chromone

5-Hydroxy-2-(2-phenylethyl)chromone(1) was synthesized from 2,6-dihydroxyacetophenone(7) obtained via four-steps resorcinol-reacting with phenylpropionic acid,the procedures involved are Baker-Venkataraman rearrangement and cyclization which are easy to conduct,the overall yield is 32%.     

Natural occurring 2-(2-phenylethyl) chromones,structure elucidation and biological activities

2-(2-Phenylethyl) chromone (PEC), an uncommon class of chromones, possesses a phenylethyl substituent at the C2 position. They have been isolated from a few plant species. They have promising biological activities such as neuro-protective, cytotoxic, acetylcholinesterase inhibitory, antibacterial and anti-inflammatory. This review focuses on the naturally occurring PEC derivatives, their sources, physical and spectral data, as well as biological activities.     

Stereospecific synthesis of N-(1-phenylethyl)-2,4,5-triphenyloxazolidines

Treatment of the diastereoisomeric N-(1-phenylethyl)-1,2-diphenyl-2-aminoethanols with benzaldehyde yields stereospecifically N-(1-phenylethyl)-2,4,5-triphenyloxazolidines with four chiral centers. The configurations of these oxazolidines are established through their ring-opening reactions with methylmagnesium iodide and subsequent oxidation with lead tetracetate.