Sesquiterpenoids and 2-(2-Phenylethyl)chromone Derivatives from the Resinous Heartwood of Aquilaria sinensis

One novel spirolactone,aquilarisinolide(1),three new sesquiterpenoids,(2R,4S,5R,7R)-2-hydroxyeremophila-9,11-dien-8-one(2),(1R,4S,5S,7R,11R)-13-hydroxyepidaphnauran-9-en-8-one(3),and(4R,5S,7R,8S,10S,13R)-8,13-dihydroxyrotunda-1,11-dien-3-one(4),together with 13 known compounds(5-17)were isolated from the resinous heartwood of Aquilaria sinensis(Thymelaeaceae).The structures of the new compounds were elucidated based on the analysis of NMR and MS data and theoretical calculations their ECD spectra.The isolated compounds were evaluated for their protective activities against PC12 cell injury induced by corticosterone(CORT)and 1-methyl-4-phenylpyridine ion(MPP+),as well as inhibitory activities against BACE1.Compound 4,5,6-dihydroxy-2-(2-phenylethyl)chromone(5),daphnauranol B(7),6-methoxy-2-[2-(3-methyoxyphenyl)ethyl]chromone(10),isoagarotetrol(14),and 1-hydroxy-1,5-diphenylpentan-3-one(16)showed significant protective effects on CORT-induced injury in PC12 cells at a concentration of 20μM(P<0.001).Isoagarotetrol(14)showed a significant protective effect on MPP+-induced injury in PC12 cells at a concentration of 20μM(P<0.001),while compound 4 showed a moderate activity(P<0.01).The BACE1-inhibitory activities of all tested compounds were very weak with less than 30%inhibition at a concentration of 20μM.

Crystal Structure,Thermal Behavior and Luminescence of a New Dimeric Manganese(Ⅱ) Complex Constructed with 3-Carboxy-1-carboxymethyl-2-oxidopyridinium

A new dimeric Mn（Ⅱ） complex,namely,[Mn（L）（PIP）]_2·H_2O（1）,was synthesized under hydrothermal condition（H_2L = 3-carboxy-1-carboxymethyl-2-oxidopyridinium and PIP = 2-（pyridin-3-yl）-1H-imidazo[4,5-f][1,10]phenanthroline）.It crystallizes in triclinic,space group P1 with a = 9.2037（13）,b = 9.6794（13）,c = 14.649（3） A,α = 94.858（3）,β = 94.928（3）,γ = 114.468（2）o,V = 1172.9（3） A^3,Z = 1,C_（52）H_（34）Mn_2N_（12）O_（11）,Mr = 1112.79,Dc = 1.575 g/cm^3,F（000） = 568,μ（Mo Ka） = 0.618 mm^-1,R = 0.0432 and w R = 0.1151.In 1,two L anions bridge two Mn（Ⅱ） atoms to give a dimeric [Mn（L）（PIP）] unit with the Mn···Mn distance of 3.009（2） A.The two PIP ligands are located on both sides of the dimer,which provides suitable π-π stacking interactions between PIP ligands.By these π-π stacking interactions,adjacent dimers are extended into a two-dimensional supramolecular layer.Further,the strong N–H···O hydrogen bond stabilizes the supramolecular layer structure of 1.Moreover,the thermal behavior and luminescent property of 1 have been studied.

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

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

Five new 2-(2-phenylethyl)chromone derivatives and three new sesquiterpenoids from the heartwood of Aquilaria sinensis, an aromatic medicine in China

Five new 2-(2-phenylethyl)chromone derivatives,(5S,6R,7R,8S,7ʹR)-7ʹ-hydroxyagarotetrol(1),(5S,6R,7R,8S,7ʹS)-7ʹ-hydroxyagarotetrol(2),(6S,7S,8R)-2-[2-(4-methoxyphenyl)ethyl]-6,7,8-trihydroxy-5,6,7,8-tetrahydrochromone(3),(6S,7S,8R)-2-(2-phenylethyl)-6,7,8-trihydroxy-5,6,7,8-tetrahydrochromone(4),(5S,6R,7S,8R)-2-(2-phenylethyl)-5,6,7-trihydroxy-5,6,7,8-tetrahydro-8-[2-(2-phenylethyl)-7-methoxychromonyl-6-oxy]chromone(5),three new sesquiterpenoids,(4S,5S,7S,8S,10S,13R)-7,8,13-trihydroxyrotunda-1,11-dien-3-one(6),(4S,5S,7S,8S,10S,13S)-7,8,13-trihydroxyrotunda-1,11-dien-3-one(7),and(4R,5S,7S,8S,10S,13S)-7,8,13-trihydroxyrotunda-1,11-dien-3-one(8),along with 14 known compounds were isolated from the resinous heartwood of Aquilaria sinensis(Thymelaeaceae).The chemical structures of these new compounds were elucidated by 1D and 2D NMR and MS data,single-crystal X-ray diffraction analysis,and electronic circular dichroism(ECD)calculations.The neuroprotective activities of these isolates were evaluated using an in vitro model of rat adrenal pheochromocytoma(PC12)cell injury induced by corticosterone.At concentrations from 5 to 40μM,compounds 4 and 6,agarotetrol(9),and 6-hydroxy-2-(2-phenylethyl)chromone(17)showed significant protective activities against corticosterone-induced PC12 cell injury(P<0.001).

国产人工打洞沉香中一个新的2-(2-苯乙基)色酮二聚体

为进一步研究国产人工打洞法所结沉香中的化学成分,本研究采用硅胶柱色谱、Sephadex LH-20、半制备高效液相等色谱方法从其乙酸乙酯萃取物中分离纯化得到2个单体化合物。根据核磁共振(NMR)、质谱(MS)等波谱数据分别鉴定为2-(2-苯乙基)色酮二聚体(+)-3′,3′′′-dihydroxy-4′,4′′′-dimethoxyaquisinenone G(1)和aquilasinenone F(2),其中化合物1为新化合物。抗氧化活性测试结果表明,化合物1和2都对DPPH自由基具有一定的清除能力,其中化合物2的IC_(50)值为(64.6±1.6)mol/L,阳性对照为L(+)-抗坏血酸。

A New Chromone Derivative from Stellera chamaejasme L

A new chromone derivative, 3-[1- (2, 4, 6-trihydroxyphenyl) 3-di-(4-hydroxyphenyl) 1-propanone-2-yl] 5,7-dihydroxy-8-di(4-hydroxyphenyl)methyl-4H-1-benzopyran-4-one, named as isomohsenone was isolated from the roots of Stellera chamaejasme L. together with known chamaechromone. Its structure was determined by the analysis of MS and NMR data, especially 2D NMR spectra.

A New Cadmium(Ⅱ) Dimer Constructed by 1,10-Phenanthroline Derivative and Chlorine Anions: Syntheses, Crystal Structure and Photoluminescence

In this work, a new Cd（Ⅱ） dimeric compound, [Cd（Cl）2（L）（H2O）]2 （1, L = 2-（4- fluorophenyl）-lH-imidazo[4,5-f][1,10]phenanthroline）, has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a = 8.944（2）, b = 18.781（5）, c = 10.904（3） A, β = 91.392（4）°, V = 1831.2（8） A^3, Z = 2, C3sH26Cd2F2C14Cl4N8O2, Mr = 1031.27, Dc = 1.870 g/cm3, F（000） = 1016, μ（MoKα） = 1.513 mm^-1, R = 0.0532 and wR = 0.1407. Each Cd（ll） atom is in an octahedral coordination sphere, completed by two nitrogen atoms from one L ligand, two chlorine anions, and one water oxygen atom. Two chlorine anions bridge two Cd（Ⅱ） atoms to give a dimer [Cd（Cl）2（L）（H2O）]2. Adjacent dimers are stacked by one type of π…π interactions among L ligands to generate a 1D supramolecular chain. Further, the 1D supramolecular chains are stacked by another type of π…π interactions among L ligands to give a 2D supramolecular layer. Finally, the luminescent property of 1 has been studied in solid state at room temperature.

2-(2-Phenylethyl)chromones from Endophytic Fungal Strain Botryosphaeria rhodina A13 from Aquilaria sinensis

Objective To study the characteristic 2-（2-phenylethyl）chromone components of endophytic fungal strain of Aquilaria sinensis by solid culture. Methods The compounds were isolated by various chromatographic methods such as silica gel, reverse-phase silica gel, Sephadex-LH20 column chromatography as well as crystallization. Results Seven 2-（2-phenylethyl）chromone analogues were isolated from the solid culture of Botryosphaeria rhodina A13. Their structures were established by spectral data as well as physicochemical properties, and identified as 6-hydroxy-7-methoxy-2-（2-phenylethyl）chromone （1）, 6,7-dimethoxy-2-（2-phenylethyl） chromone （2）, （5S,6R,7S,8R）-2-（2-phenylethyl）-5,6,7,8-tetrahydrchromone （3）, 6- hydroxy-2-（2-phenylethyl）chromone （4）, 4＇-hydroxy-2-（2-phenylethyl）chromone （5）, 6-methoxy-2-phenethyl-4H-chromen-4-one （6）, and 6-methoxy-2-（4＇-methoxy-phenethyl）-4H-chromen-4-one （7）. Conclusion All of the compounds are isolated for the first time from the genus Botryosphaeria. This research opens up a new vista to produce the characteristic components of agarwood by endophytic fungi.

丝沉香中2个α-葡萄糖苷酶抑制活性的2-(2-苯乙基)色酮二聚体

目的研究菲律宾产丝沉香Aquilaria filaria的化学成分。方法采用硅胶、凝胶、半制备高效液相色谱等多种色谱技术分离丝沉香的化学成分,通过高分辨质谱、核磁共振等波谱学方法鉴定化合物结构,采用改进后的4-硝基苯基-β-D-吡喃葡萄糖苷(4-nitrophenyl-β-D-glucopyranoside,pNPG)法测试化合物的α-葡萄糖苷酶抑制活性。结果从菲律宾产丝沉香中分离鉴定了2个2-(2-苯乙基)色酮二聚体,分别为aquifilarone N(1)和diaquilariachrome B(2)。化合物1和2均具有α-葡萄糖苷酶抑制活性,半数抑制浓度(median inhibition concentration,IC_(50))值分别为(14.33±0.38)μmol/L和(39.53±2.09)μmol/L。结论化合物1为新化合物,化合物2为首次从丝沉香中分离得到。