双甲基酮的制备

从壬二酸、癸二酸和十一碳烯酸出发，经脱羰端烯化反应、Wacker反应制备了2，6－康二酮，2，7－辛二酮，2，9－苯二酮。所得化合物的结构经IR,^1H NMR,^13C NMR和MS证实。     

长叶暗罗中克罗烷型二萜及其抗炎作用

对长叶暗罗茎的化学成分进行研究,分离得到4个新的克罗烷型二萜类化合物,通过NMR、HR-ESI-MS等多种现代波谱技术鉴定为:2-氧代-14,15,16-降三碳克罗烷-3-烯-13-酸(1)、2-氧代-14,15,16-降三碳克罗烷-3-烯-13-甲酯(2)、2-氧代-14,15,16-降三碳克罗烷-3,11E-二烯-13-酸(3)、2-氧代-16-羟基-克罗烷-3,13Z-二烯-15-酸(4).其中,化合物1～3为降三碳克罗烷型二萜,所有化合物均表现出一定的抗炎活性, IC50值范围为9.24～18.82μmol/L.     

DBU及DBN与丙炔酸甲酯的迈克尔型加成及其产物的核磁共振谱学研究

1,8-二氮杂二环[5,4,0]十一碳-7-烯(DBU及1,5-二氮杂二环[4,3,0]壬碳-5-烯与丙炔酸甲酯反应可生成成环化合物。通过对成环产物的^1H NMR、^1H-^1H COSY、^13C NMR谱的分析,讨论了其化学位移及J-偶合特征。同时研究了整个反应可能的历程和机理。     

Δ^5-3β-取代-5-甾烯并取代[17，16-c]吡唑（异嗯唑）啉-5′-酮类化合物的合成

3β-取代-5-甾烯-17-酮与碳酸二甲酯经克莱森缩合所得产物再分别与肼或羟胺反应，合成了几种新的Δ^5-3β-取代-5-甾烯并-1′-取代[17，16-c]吡唑啉-5′-酮和Δ^5-3β-取代-5-甾烯并[17，16-c]异噁唑啉-5′-酮化合物，其结构均经元素分析，IR和^1H NMR确证。     

双环[10,3,0]十五碳-1(12)-烯-13-酮系列化合物的合成

以多聚磷酸为催化剂,通过环十二碳烯和α,β-不饱和酸的反应,合成了十个双环[10.3.0]十五碳-1(12)-烯-13-酮系列化合物,研究了合成反应的条件及产物的分离提纯方法,并测定了它们的紫外光谱、红外光谱以及~1H核磁共振谱。     

臭灵丹化学成分研究II

从臭灵丹(LaggeraPterodonta(DC)Benth)地上部分水煎浓缩液的氯仿提取液中,分离出四个化合物(1-4),1和2为倍半萜化合物,3和4为黄酮化合物,经紫外光谱、红外光谱、核磁共振^1H谱、^1^3C谱、^1H-^1Hcosy谱及质谱测定,分别为臭灵丹酮酸、冬青酸、洋艾素和金腰素乙。化合物1具有桉烷型倍半萜结构,为Δ^4^,^1^1-桉双烯-3-酮-13-酸,它是一新化合物。     

臭灵丹化学成分研究II

从臭灵丹(LaggeraPterodonta(DC)Benth)地上部分水煎浓缩液的氯仿提取液中,分离出四个化合物(1-4),1和2为倍半萜化合物,3和4为黄酮化合物,经紫外光谱、红外光谱、核磁共振^1H谱、^1^3C谱、^1H-^1Hcosy谱及质谱测定,分别为臭灵丹酮酸、冬青酸、洋艾素和金腰素乙。化合物1具有桉烷型倍半萜结构,为Δ^4^,^1^1-桉双烯-3-酮-13-酸,它是一新化合物。     

18-甲基腺甾烯酮一类物的酶催化羟化

18-甲基-11α-羟基腺甾-4-烯-3,17-双酮是合成高效口服避孕药的重要中间体。试用黑根霉酶羟化引进11α-羟基于18-甲基-19-失碳雌甾-4-烯-3,17-双酮,得到包括该化合物在内的几种不同位置羟基产物的混合物。改用赭曲霉酶羟化同一底物也得到包括11α-羟基在内的几种不同位置羟基产物的混合物。而用赭曲霉催化羟化18-甲基-17β-羟基腺甾-4-烯-3-酮时,首次得到15α-羟化的主要产物和7β羟化的次要产物。前者可用来合成另一类高效口服避孕药△^15-D-18-甲基炔诺酮。     

18-甲基腺甾烯酮一类物的酶催化羟化

18-甲基-11α-羟基腺甾-4-烯-3,17-双酮是合成高效口服避孕药的重要中间体。试用黑根霉酶羟化引进11α-羟基于18-甲基-19-失碳雌甾-4-烯-3,17-双酮,得到包括该化合物在内的几种不同位置羟基产物的混合物。改用赭曲霉酶羟化同一底物也得到包括11α-羟基在内的几种不同位置羟基产物的混合物。而用赭曲霉催化羟化18-甲基-17β-羟基腺甾-4-烯-3-酮时,首次得到15α-羟化的主要产物和7β羟化的次要产物。前者可用来合成另一类高效口服避孕药△^15-D-18-甲基炔诺酮。     

远东疣柄牛肝菌的化学成分

从远东疣柄牛肝菌(Leccinum extremiorientale)子实体中提取分离得到13个 化合物，通过理化常数和波谱数据分析，它们的结构被鉴定为：麦角甾-7，22-二 烯-3β，5α，6β-三醇（1），麦角甾醇过氧化物（2），麦角甾醇（3），麦角甾 -4，6，8（14），22-四烯-3-酮（4），麦角甾-5，7-二烯-3β-醇（5），棕榈酸 （6），（2S，3S，4R，2’R）-2-（2’-羟基二十四碳酰胺）十八烷-1，3，4-三 醇（7），脑苷脂B（8），脑苷脂D（9），尿嘧啶（10），肌苷（11），腺苷（12 ），D-阿洛醇（13），利用2D NMR（~1H-~1H COSY，HMBC，HMQC）技术首次对化合 物8和9的氢谱和碳谱数据进行了全归属。在浓度为100 μg/mL时，化合物2，7和8 表现出选择性地抗蛇毒Crotalus adamenteus分泌的磷脂酶A_2活性，而对蜂毒 Apis mellifcra磷脂酶A_2却无活性。此外，远东疣柄牛肝菌提取物对粘虫拒食率 和小莱蛾死亡率分别为67%和55%。     

The Formation of Methyl Ketones during Lipid Oxidation at Elevated Temperatures

Lipid oxidation and the resulting volatile organic compounds are the main reasons for a loss of food quality. In addition to typical compounds, such as alkanes, aldehydes and alcohols, methyl ketones like heptan-2-one, are repeatedly described as aroma-active substances in various foods. However, it is not yet clear from which precursors methyl ketones are formed and what influence amino compounds have on the formation mechanism. In this study, the formation of methyl ketones in selected food-relevant fats and oils, as well as in model systems with linoleic acid or pure secondary degradation products (alka-2,4-dienals, alken-2-als, hexanal, and 2-butyloct-2-enal), has been investigated. Elevated temperatures were chosen for simulating processing conditions such as baking, frying, or deep-frying. Up to seven methyl ketones in milk fat, vegetable oils, and selected model systems have been determined using static headspace gas chromatography-mass spectrometry (GC-MS). This study showed that methyl ketones are tertiary lipid oxidation products, as they are derived from secondary degradation products such as deca-2,4-dienal and oct-2-enal. The study further showed that the position of the double bond in the precursor compound determines the chain length of the methyl ketone and that amino compounds promote the formation of methyl ketones to a different degree. These compounds influence the profile of the products formed. As food naturally contains lipids as well as amino compounds, the proposed pathways are relevant for the formation of aroma-active methyl ketones in food.     

Development of 4,4'-substituted-XylBINAP ligands for highly enantioselective hydrogenation of ketones

[reaction: see text] A family of 4,4'-substituted-xylBINAPs was synthesized in multistep sequences and characterized by NMR spectroscopy and mass spectrometry. Ru(diphosphine)(diamine)Cl(2) complexes based on these 4,4'-substituted-xylBINAPs and chiral diamines (DPEN and DAIPEN) were synthesized by treatment of [(benzene)RuCl(2)](2) with 4,4'-substituted-xylBINAP followed by chiral diamine, and characterized by (1)H and (31)P NMR spectroscopy and mass spectrometry. These Ru complexes were used for asymmetric hydrogenation of aromatic ketones in a highly enantioselective manner with complete conversion. With 0.1% catalyst loading, complete conversion and enantioselectivity greater than 99% were obtained for most of the aromatic ketones examined. These Ru catalysts thus gave the highest ee for asymmetric hydrogenation of aromatic ketones among all of the catalysts reported in the literature. A single-crystal X-ray diffraction study of Ru[(R)-L(4)()][(R,R)-DPEN]Cl(2) indicated that the 4-methyl group of the naphthyl ring and the methyl groups of the two xylyl moieties form a fence on the opposite side of the DPEN ligand of the Ru center. These three methyl groups will have significant repulsive interactions with the bulky aryl ring of the hydrogen-bonded aromatic ketone in the disfavored transition state. These results support our hypothesis of combining dual modes of enantiocontrol (i.e., the substituents on 4,4'-positions of the binaphthyl framework and the methyl groups on the bis(xylyl)phosphino moieties) to achieve higher stereoselectivity in the hydrogenation of aromatic ketones.     

Guaiane-type sesquiterpenoid glucosides from Gardenia jasminoides Ellis

Two new guaiane-type sesquiterpenoid glucosides (1 and 2) were isolated from the fruit of Gardenia jasminoides Ellis. Their structures were elucidated to be (1R,7R,10S)-11-O-β-D-glucopyranosyl-4-guaien-3-one (1) and (1R,7R,10S)-7-hydroxy-11-O-β-D-glucopyranosyl-4-guaien-3-one (2) by one- and two-dimensional NMR techniques ((1)H NMR, (13)C NMR, HSQC, HMBC and NOESY), MS, CD spectrometry and chemical methods.     

Novel Route to 4‐(Adamantan‐1‐yl)quinoline Derivatives Based on the Friedländer Condensation

2,3,4‐Trisubstituted quinolines, substituted with adamantan‐1‐yl or (adamantan‐1‐yl)methyl in the 4‐position, were prepared from the corresponding admantan‐1‐yl 2‐aminophenyl ketones or admantan‐1‐ylmethyl 2‐aminophenyl ketones and ketones with an α‐CH₂ group. These reactions were carried out under neat conditions or in toluene, and the products were obtained in moderate‐to‐excellent yields. The scope and limitations of the examined procedures are discussed. All new compounds are fully characterized by IR and NMR spectroscopy and mass spectrometry. The molecular structures of five new quinolines, obtained via single‐crystal X‐ray diffraction analyses, are discussed.     

An NMR method for assigning relative stereochemistry to beta-hydroxy ketones deriving from aldol reactions of methyl ketones

We describe a simple 1H NMR analysis that permits the stereochemistry of beta-hydroxy ketones to be assigned by visual inspection of the ABX patterns for the alpha-methylene unit of the beta-hydroxy ketone in the 1H NMR spectra. This method has been verified by application to a wide range of beta-hydroxy ketones deriving from aldol reactions of chiral aldehydes with a variety of chiral and achiral methyl ketone enolates (see Tables 1 and 2). The stereochemistry of 54 of these compounds have been assigned by rigorous chemical methods.     

Regioselective Synthesis of 4-Acetyl-and 5-Acetyl-3-methylisoxazole: Their Conversion into Silyl-and Methyl Enol Ethers

Acetonitrile oxide reacts regioselectively with 3-buten-2-one and (E)-4-methoxy-3-buten-2-one to give 5-acetyl-2 and 4-acetyl-3-methylisoxazole 3, respectively. Treatment of ketones 2 and 3 with trimethylsilyl trifluoromethanesulfonate gave the silyl enol ethers 4 and 5, whereas the methyl enol ethers 8 and 9 were obtained via elimination of methanol from the corresponding dimethyl ketals.     

The Clemmensen Reduction of α, β-Unsaturated Ketones

Eleven structurally different α, β-unsaturated ketones were subjected to the Clemmensen reduction under anhydrous conditions using amalgamated zinc, hydrogen chloride in a solution of ethyl ether, and acetic anhydride. In all cases but one the formation of cyclopropyl acetates was observed. 4-Methyl-3-penten-2-one, methyl vinyl ketone, 2-isopropylidene-1-cyclopentanone, and 2-cyclohepten-1-one led to substituted cyclopropyl acetates. Stereospecific reactions were found with 2-ethylidene-1-cyclopentanone, 2-benzylidene-1-cyclohexanone, and methyl 1-cyclohexenyl ketone, whereas 3-penten-2-one, 3-methyl-3-buten-2-one, and 2-methyl-2-cyclohexen-1-one afforded mixtures of the isomeric cyclopropyl acetates. These results are interpreted in terms of the intital formation of an allylic anion which undergoes electrocyclic closure. A stereospecific course is followed when geometric constraints permitted. Exceptions are discussed.     

8-羟基喹啉席夫碱衍生物及其金属配合物的合成及荧光性质研究

设计合成了三种新的8-羟基喹啉席夫碱衍生物4-(8-羟基喹啉-5-亚胺甲基)-7-甲氧基苯并吡喃-2-酮(3a),4-(8-羟基喹啉-5-亚胺甲基)-7-己氧基苯并吡喃-2-酮(3b)和4-(8-羟基喹啉-5-亚胺甲基)-7-十八烷氧基苯并吡喃-2-酮(3c)及其铝、锌配合物,产物结构经1H(13C)NMR,MS,HRMS,IR和元素分析表征,研究了它们的荧光发光性能.     

Synthesis of new 2-aryl-6-styryl-2,3-dihydropyridin-4(1H)-one derivatives from curcuminoids

Series of new 2-aryl-6-styryl-2,3-dihydropyridin-4(1H)-one derivatives were synthesized in acceptable to good yields by treatment of the curcuminoids with aqueous ammonia,the mechanism was proposed.By modification of the primary products,total 13 new compounds were obtained.The structures of all products were elucidated by spectroscopy analysis including HR-MS,~1H NMR and ~(13)C NMR.     

New ent-Isopimarane Diterpene from Mangrove Excoecaria agallocha L.

A new ent-isopimarane diterpenoid,Agallochaone A(1),together with the known 8,13-epoxy-14-labden-3-one(2)and Excoecarin B(3)were isolated from the whole plant of mangrove Excoecaria agallocha L.and identified on the basis of a detailed spectral analysis,including 2D NMR spectrometry and HRESI-MS.