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.     

New 2-(2-phenylethyl)chromone derivatives from agarwood and their inhibitory effects on tumor cells

Abstract

Two new chromone derivatives, 7-hydroxy-2-[2-(3'-methoxy-4'-hydroxyphenyl)-ethyl]chromone (1), and 6,7-dimethoxy-2-[2-(3'-hydroxyphenyl)-ethyl]chromone (2) were isolated from the EtOH extract of agarwood of Aquilaria sinensis, together with eleven known analogues. Their structures were established by detailed HR-ESIMS, 1D and 2D NMR spectroscopic analysis, as well as comparison with the literature data. Selected the isolates (1, 2, 4–8, 10, 11) were tested for their antitumor activities against SMMC-7721, MGC-803 and OV-90 cell lines using the MTT method with cisplatin and paclitaxel as the positive control. All the tested compounds showed weak cytotoxic activities with IC₅₀ values ranged from 18.82 to 37.95 µg/ml.     

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.     

A new cytotoxic 2-（2-phenylethyl）chromone from Chinese eaglewood

A new compound 8-chloro-5,6,7-trihydroxy-2-（3-hydroxy-4-methoxyphenethyl）-5,6,7,8-tetralaydro-4H-chromen-4-one （1） was isolated from the Chinese eaglewood [Aquilaria sinensis （Lour.） Gilg]. Its structure was elucidated on the basis of spectral data. Compound I showed cytotoxicity against human gastric cancer cell line （SGC-7901） in vitro by MTT method with the IC50 value of 14.6 μg/mL.     

Synthesis of 3-(N-arylcarbamoyl)chromones from 2-hydroxyarylaminoenones and isocyanates

Russian Chemical Bulletin - A new method for the synthesis of 2-unsubstituted and 2-substituted 3-(N-arylcarbamoyl)-chromones by the reaction of 3-dimethylamino-1-(2-hydroxyaryl)prop-2-en-1-ones...     

2,5-diphenyl-1,4-(trifluoromethylsulfonyl)piperazine from N-(2-bromo-2-phenylethyl)trifluoromethanesulfonamide

Russian Journal of Organic Chemistry -     

2-(Polyfluoroalkyl)chromones. 15. Transformation of 3-chloro-2-(polyfluoroalkyl)chromones into benzofuran derivatives by hydroxylamine

The reactions of 3-chloro-2-(polyfluoroalkyl)chromones with hydroxylamine in the presence of sodium acetate proceed with ring contraction to form benzofuran derivatives.     

3-[5-(2-Ethoxycarbonyl)benzofuryl]chromones

The previously undescribed 3-(5-benzofuryl)chromones and their derivatives were obtained, and their UV and IR spectra were measured.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1324–1328, October, 1972.     

Reactions of 3-(polyfluoroacyl)chromones with hydroxylamine. The first synthesis of 3-cyano-2-(polyfluoroalkyl)chromones

Reaction of 3-(polyfluoroacyl)chromones with hydroxylamine proceeds via nucleophilic 1,4-addition followed by opening of the pyrone ring and subsequent cyclization to 4-(polyfluoroalkyl)-4H-chromeno[3,4-d]isoxazol-4-ols in good yields. On treatment with trifluoroacetic acid, the isoxazole ring of this annulated heterocyclic system opens to give 3-cyano-2-(polyfluoroalkyl)chromones. Reaction of 3-(polyfluoroacyl)chromones with hydroxylamine hydrochloride occurs only at the carbonyl carbon atom connected to the R^F group to give the corresponding oximes in low yields.     

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%.     

Four new 2-(2-phenylethyl)chromone derivatives from withered wood of Aquilaria sinensis

Four new chromone derivatives, 5-hydroxy-6-methoxy-2-(2-phenylethyl)chromone (1), 6-hydroxy-2-(2-hydroxy-2-phenylethyl)chromone (2), 8-chloro-2-(2-phenylethyl)-5,6,7-trihydroxy-5,6,7,8-tetrahydrochromone (3), 6,7-dihydroxy-2-(2-phenylethyl)-5,6,7,8-tetrahydrochromone (4) were isolated from the MeOH extract of withered wood of Aquilaria sinensis, together with seven known constituents of agarwood.     

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.     

2-R-7-Hydroxy-8-methyl-3-(2-quinolyl)chromones

By condensation of 2-methyl resorcinol with 2-quinolyl acetonitrile, we have synthesized α-(2-quinolyl)-2,4-dihydroxy-3-methylacetophenone, which when reacted with carboxylic acid anhydrides followed by hydrolysis yields 2-R-7-hydroxy-8-methyl-3-(2-quinolyl)chromones.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 407–415, March, 2005.