2-甲基-2-苯基-1,3-二硫环庚烷的合成及香气研究

以硫代硫酸钠、1,4-二氯丁烷和苯甲醛为原料,用BunteSalts法,经过一步操作合成了2-甲基-2-苯基-1,3-二硫环庚烷,其收率为60%。实验表明,当1,4-二氯丁烷与硫代硫酸钠以等摩尔投料时,可减少盐酸用量,并能避免单质硫的析出而影响分离提纯。用IR、1HNMR、MS证实了目标化合物结构,并对2-甲基-2-苯基-1,3-二硫环庚烷的香气进行了鉴定,结果表明2-甲基-2-苯基-1,3-二硫环庚烷具有浓郁的葱蒜气味,其阈值在水中为0.24×10-6,在植物油中为15.00×10-6。     

1，3-二硫环庚烷的合成及香气研究

以硫代硫酸钠、1,4-二氯丁烷和甲醛为原料为原料,用BunteSalts法,经过一步操作合成了1,3-二硫环庚烷,其收率为63%。实验表明,当1,4-二氯丁烷与硫代硫酸钠以等摩尔投料时,可减少盐酸用量,并能避免单质硫的析出而影响分离提纯。用IR、1HNMR、MS证实了目标化合物结构,并对1,3-二硫环庚烷的香气进行了鉴定,结果表明1,3-二硫环庚烷具有浓郁的葱蒜气味,其阈值在水中为0.25×10-6,在植物油中为13.00×10-6。     

1-（2，6-二氯-4-三氟甲基苯基）-3-乙酰氨基-5-氨基吡唑及其合成及晶体结构

【摘要】2,6-二氯-4-三氟甲基苯胺经重氮化后,与2,3-二氰基丙酸乙酯反应,碱性关环得到中间体1-f2,6-二氯-4-三氟甲基苯基）-3-氰基-5-氨基吡唑（1）,1与双氧水在碱性条件下反应得到1的3-乙酰氨基化合物2。通过元素分析,红外光谱,核磁共振氢谱,核磁共振破谱等手段对其结构进行了表征。用x射线单晶衍射测定了化合物2的晶体结构。2属于单斜晶系,C2／c空间群,晶胞参数a=19．190（4）nm,b=14．458（3）nm,c=10,169（2）nm,α=90．00°,β=103．57（3）°,γ=90．00°,V=2742．6（9）nm^3,Z=8,R=0．0479,wR=0．1289°     

食用香料糠基2-甲基-3-呋喃基二硫醚的合成

首先以α-糠基氯和硫代硫酸钠反应制备Bunte盐,然后Bunte盐与2-甲基-3-呋喃硫醇在碱性条件下反应合成了产品糠基2-甲基-3-呋喃基二硫醚.较佳合成工艺为:硫代硫酸钠与α-糠基氯摩尔配比4:1,氢氧化钠用量8.0 g.反应时间1 h.减压蒸馏后,计算两步反应总产率为31.7%,气相色谱分析糠基2-甲基-3-呋喃基二硫醚相对含量为78.4%.进一步硅胶柱色谱纯化,糠基2-甲基-3-呋喃基二硫醚的结构用质谱、红外光谱、核磁共振进行了确认.     

4-溴-1-（2，6-二氯-4-三氟甲基苯基）-3-氰基-5-（4-硝基苯基）亚氨基吡唑的合成

1-（2,6-二氯-4-三氟甲基苯基）-3-氰基-5-氨基吡唑（1）以NBS（N-溴代丁二酰亚胺）为溴化试剂制得4-吡吡唑化合物（2）,2与对硝基苯甲醛在酸性条件下反应得到席夫碱3。研究了化合物1与NBS的反应及其席夫碱的合成,通过元素分析、红外光谱、核磁共振氢谱、核磁共振碳谱等手段对其结构进行了表征。用X射线单晶衍射测定了化合物3的晶体结构。     

磷钨酸催化合成1；3-二硫杂环戊烷类香料化合物

以磷钨酸为催化剂,乙二硫醇与异戊醛在苯中回流,合成了2-异丁基-1,3-二硫杂环戊烷。研究了乙二硫醇与异戊醛物质的量比、催化剂用量、反应时间等因素对反应收率的影响。优化条件为:乙二硫醇与异戊醛投料物质的量比为1.8,催化剂用量占反应物料总质量的2.0%,反应时间2.5h。按类似条件合成了2-甲基-2-丁基-1,3-二硫杂环戊烷、1,4-二硫杂螺[4.4]壬烷、(2′-甲基-1′,3′-二硫杂-2-环戊基)乙酸乙酯和1,3-二(1′,3′-二硫杂-2'-环戊基)丙烷。采用FTIR、1HNMR和GC-MS确定了产品结构。     

1-(2,6-二氯-4-三氟甲基苯基)-3-腈基-5-氨基吡唑及其与芳醛缩合产物的合成

2,6-二氯-4-三氟甲基苯胺经重氮化后与2,3-二腈基丙酸酯反应合成了1-(2,6-二氯-4-三氟甲基苯基)-3-腈基-5-氨基吡唑(1),1与各种含有芳香结构的醛发生缩合反应,生成了对应的席夫碱2。通过元素分析,红外光谱,核磁共振氢谱,核磁共振碳谱,质谱等手段对它们的结构进行了表征。     

三-（1-硫代-1-硫杂-2，6，7-三氧杂双环-[2．2．2]-辛烷基-4-亚甲基）磷酸酯的合成及表征

以季戊四醇、三氯硫磷、三氯氧磷为原料合成了新型的笼状的膨胀型阻燃剂三-（1-硫代-1-硫杂-2，6，7-三氧杂双环-[2．2．2]-辛烷基-4-亚甲基）磷酸酯，探讨了工艺条件，通过FTIR、^1HNMR对其结构进行了表征，用热重（TG）和差热分析（DSC）对其热性能进行了研究。     

2-取代-1，3-硫杂环戊烷香料的合成和香气评价

以醛／酮与1，2-乙二硫醇或1，2-丙二硫醇在对甲苯磺酸催化下反应，合成了10种2-取代-1，3-二硫杂环戊烷，产率62．8％～87．8％；其中，2-正丙基-1，3-二硫杂环戊烷产率达87．8％，纯度99．5％。经元素分析、FTIR、GC-MS和’HNMR确定了10种产物的结构。香气评价结果表明：合成的2-正丙基-1，3-二硫杂环戊烷具有花香、肉汤香气，可用于食品香精和调味料中；其余9种2-取代-1，3-二硫杂环戊烷具有肉香、葱蒜香和萝卜香。     

固相微萃取-气相色谱质谱联用分析花椒挥发性成分

研究不同加工方式下花椒香气的变化。以陕西韩城市产花椒为原料,利用固相微萃取-气相色谱质谱联用技术分析焙烤花椒和风干花椒中的挥发性成分。结果从焙烤花椒中共鉴定出48种挥发性成分,其中主要挥发性成分为α-蒎烯(4.14%)、6,6-二甲基-2-亚甲基-双环[3.1.1]庚烷(5.63%)、1-甲基-4-(1-甲乙基)-1,4-环己二烯(3.20%)、1,7,7-三甲基-三环[2.2.1.0(2,6)]庚烷(6.96%)、β-水芹烯(9.47%)、甲酸(8.50%)、3-蒈烯(3.62%)、3,7-二甲基-1,6-辛二烯-3-醇(3.09%)、4-甲基-1-(1-甲乙基)-3-环己烯-1-醇(5.34%)、α,α,4-三甲基-3-环己烯-1-甲醇(6.12%)、α-异戊酸松油酯(8.91%)、1,2,4α,5,8,8α-六氢-4,7-二甲基-1-(1-甲乙基)-萘(4.32%)、1-甲基-5-亚甲基-8-(1-甲乙基)-1,6-环癸二烯(5.07%);从风干花椒中共鉴定出49种挥发性成分,其中主要挥发性成分为α-蒎烯(3.38%)、6,6-二甲基-2-亚甲基-双环[3.1.1]庚烷(9.38%)、1-甲基-4-(1-甲乙基)-1,4-环己二烯(14.74%)、2-甲基-5-(1-甲乙基)-双环[3.1.0]己-2-醇(3.00%)、1,7,7-三甲基-三环[2.2.1.0(2,6)]庚烷(18.45%)、β-水芹烯(9.80%)、3,7,7-三甲基-双环[4.1.0]庚-3-烯(10.89%)、2,6-二甲基-2,4,6-辛三烯(3.37%)、3-蒈烯(3.11%)、cis-β-松油醇(5.30%)。焙烤花椒和风干花椒的挥发性成分有较大差别。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the