Indoleamine-2,3-dioxygenase 1/cyclooxygenase 2 expression prediction for adverse prognosis in colorectal cancer

AIM To evaluate indoleamine-2,3-dioxygenase 1/cyclooxygenase 2(IDO1/COX2) expression as an independent prognostic biomarker for colorectal cancer(CRC) patients.METHODS We retrospectively studied the medical records of 95 patients who received surgical resection from August 2008 to January 2010. All patients were randomly assigned to adjuvant treatment with or without celecoxib groups after surgery. We performed standard immunohistochemistry to assess the expression levels of IDO1/COX2 and evaluated the correlation of IDO1/COX2 with clinicopathological factors and overall survival(OS) outcomes.RESULTS The expression of nuclear IDO1 was significantly correlated with body mass index(P < 0.001), and IDO1 expression displayed no association with sex, age, tumor differentiation, T stage, N stage, carcinoembryonic antigen, cancer antigen 19-9, CD3+ and CD8+ tumor infiltrating lymphocytes, and COX2. In univariate analysis, we found that nuclear IDO1(P = 0.039), nuclear/cytoplasmic IDO1 [hazard ratio(HR) = 2.044, 95% confidence interval(CI): 0.871-4.798, P = 0.039], nuclear IDO1/COX2(HR = 3.048, 95%CI: 0.868-10.7, P = 0.0049) and cytoplasmic IDO1/COX2(HR = 2.109, 95%CI: 0.976-4.558, P = 0.022) all yielded significantly poor OS outcomes. Nuclear IDO1(P = 0.041), nuclear/cytoplasmic IDO1(HR = 3.023, 95%CI: 0.585-15.61, P = 0.041) and cytoplasmic IDO1/COX2(HR = 2.740, 95%CI: 0.764-9.831, P = 0.038) have significantly poor OS outcomes for the CRC celecoxib subgroup. In our multivariate Cox model, high coexpression of cytoplasmic IDO1/COX2 was found to be an independent predictor of poor outcome in CRC(HR = 2.218, 95%CI: 1.011-4.48, P = 0.047) and celecoxib subgroup patients(HR = 3.210, 95%CI: 1.074-9.590, P = 0.037).CONCLUSION Our results showed that cytoplasmic IDO1/COX2 coexpression could be used as an independent poor predictor for OS in CRC.

Synthesis and Crystal Structure of Tert-butyl 4-[(E)-4-(1,3-Dioxo-1,3-dihydro-2H-isoindol-2-yl)-1-butenyl] Benzoate

The title compound tert-butyl 4-[（E）-4-（1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl）- 1-butenyl] benzoate has been synthesized and characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 14.875（3）, b = 8.9796（13）, c = 34.736（6） A°, β = 95.981（4）°, V= 4614.4（14）A°^3, Z= 8, Dc = 1.213 g/cm^3, F（000） = 1792,μ（MoKα） = 0.084 mm^-1, R = 0.0602 and wR = 0.1445 for 4613 unique reflections with 2272 observed ones （I〉 2σ（I））. The results of crystal structure determination show that the title compound has a layer structure, and the two benzene rings in molecule are parallel to each other.

基于2-(3-吡啶基)-1H-吡唑-苯羧酸的三种镉(Ⅱ)配合物晶体结构、荧光表征和Hirshfeld表面分析

基于2⁃(3⁃吡啶基)⁃1H⁃吡唑-苯羧酸(Hppb)配体,成功合成3种溴离子参与配位的不同Cd(Ⅱ)配合物[Cd(Hppb)_(2)Br_(2)](1)、[Cd_(2)(ppb)_(2)Br_(2)](2)和[Cd(Hppb)Br_(2)]n(3),并确定了其结构特征。在3种配合物中,Cd(Ⅱ)离子、配体、溴离子的比例分别为1∶2∶2、1∶1∶1、1∶1∶2,最终得到单核(0D)、双核(0D)、一维骨架的不同结构。配合物1中的Cd(Ⅱ)配位环境为轻微扭曲的八面体几何结构,而配合物2和3的中心离子则显示出扭曲的四方锥几何结构。3个配合物的ppb-或Hppb配体的连接模式存在明显差异。在配合物1中,2个Hppb配体为μ_(1)⁃κN,N'配位模式。而在配合物2中,2个ppb-配体为μ_(2)⁃κN,N'∶κO配位模式,并且作为2个μ1,1桥连接2个Cd(Ⅱ)离子形成双核结构单元,2个Cd离子之间的距离为0.4091(4)nm。在3中,中性Hppb配体为μ_(2)⁃κN,N'∶κO配位模式,并通过μ1,6桥连接Cd(Ⅱ)离子,沿b轴形成一维无限延长的链。利用Hirshfeld表面分析和二维指纹图对这3种配合物进行了研究。此外,配合物1~3的光致发光特性表明,配位阴离子Br-对Cd(Ⅱ)配合物的荧光发射有很大影响。

2-羟基-4-(5,6-二硝基-1H-苯并[2,3-d]咪唑-2-基)苯甲酸甲酯的合成探索

以4,5-二硝基邻苯二胺和2-羟基对苯二甲酸单甲酯为起始原料,设计并成功采用一锅法合成出2-羟基-4-(5,6-二硝基-1H-苯并[2,3-d]咪唑-2-基)苯甲酸甲酯(MHDIB)。以50 mL二乙二醇二甲醚为溶剂,1.5 g的2-羟基对苯二甲酸单甲酯和2.5 g SOCl2在80℃反应2 h制2-羟基-4-氯羰基苯甲酸甲酯。室温下快速向反应体系中加入1.56 g 4,5-二硝基邻苯二胺,并于85℃反应1 h后加入3.52 g多聚磷酸,回流反应1 h后水析出粗产品,经乙醇重结晶得到纯度为93.67%的黄色针状产物,产率为17.82%。产物经IR、MS、1H NMR的准确定性和表征,作为AB型新单体的前体可应用于羟基改性PBI纤维即聚2-羟基-1,4-亚苯基-2,6-苯并[2,3-d:5',6'-d']二咪唑(H-PBI)的创新研究。

2-苯基-1,3-二氧杂环-4-戊烯-乙酸甲酯的合成

以苯甲酸、3-溴丙烯和乙酸为原料,三氟化硼乙醚为催化剂合成2-苯基-1,3-二氧杂环-4-戊烯-乙酸甲酯,包括烯丙基苯甲酸酯的制备和烯丙基苯甲酸酯的环化。考察了烯丙基苯甲酸酯与乙酸的摩尔比、反应时间、温度、催化剂用量对反应的影响。结果表明,较佳的反应条件为:取0.05 mol烯丙基苯甲酸酯,n(烯丙基苯甲酸酯)∶n(乙酸)=1.0∶1.2(摩尔比),催化剂用量为5.0%,在室温(25℃)下反应10 h,所得产品的产率在87%以上。

苯甲酸（1,2,2,6,6-五甲基）哌啶醇酯的合成研究

研究了苯甲酸甲酯,1,2,2,6,6-五甲基哌啶醇为原料进行酯交换反应合成苯甲酸（1,2,2,6,6-五甲基）哌啶醇酯。对四种催化剂的催化效果进行了考察,其中四丁基钛酸酯的催化效果最好。考察了温度、反应时间、原料摩尔比和催化剂四丁基钛酸酯的用量对反应的影响。实验结果表明：在苯甲酸甲酯甲酯与1,2,2,6,6-五甲基哌啶醇摩尔比为1∶1.1,四丁基钛酸酯的用量为反应物总质量的0.3%、反应温度为160℃、反应时间为8 h的条件下,反应收率为92.4%。

一种新型有机电致磷光材料中间体8-甲基-1-苯基-[1,2,4]三唑[4,3-a]喹啉的合成研究

以苯甲酸乙酯与水合肼反应得苯甲酰肼、再与2-氯-7-甲基喹啉得到目标产物8-甲基-1-苯基-[1,2,4]三唑[4,3-a]喹啉,其结构经1HNMR确认。考察了水合肼用量对苯甲酰肼产率的影响、不同溶剂对8-甲基-1-苯基-[1,2,4]三唑[4,3-a]喹啉产率的影响。结果表明,水合肼与苯甲酸乙酯摩尔比为2.1制备苯甲酰肼结果最佳,正丁醇作溶剂制备8-甲基-1-苯基-[1,2,4]三唑[4,3-a]喹啉效果更好。

2-(α-羟基戊基)苯甲酸钾盐的急性毒性和致突变作用研究

目的：研究2-（a-羟基戊基）苯甲酸钾盐（dl—PHPB）的急性毒性及致突变性。方法：急性毒性试验采用Bliss法，昆明小鼠分为5组，每组10只，雌雄各半，分别按256．0、286．3、320．0、357．8、400．0、447．2mg／kg静脉注射dl—PHPB，观察注射后至给药后14d动物的毒性反应性质及程度，计算半数致死剂量（LD50）及95％可信限；Ames试验采用平板掺入预培养法，选用鼠伤寒沙门氏菌株TA97、TA98、TA100和TA102，每皿10．5～5000．0μg浓度范围内，检测加和不加S9条件下对Ames菌的致突变性；微核试验采用雄性昆明小鼠，分为3组，每组6只，分别按23．3、70、210mg／kg单次静脉注射dl—PHPB，注射后24h计数骨髓嗜多染红细胞微核率（MNPCEs）；体外染色体畸变试验在加和不加S9条件下，检测11．0～88．0μg／mL dl—PHPB对CHL细胞染色体畸变率的影响。结果：小鼠静脉注射dl—PHPB后，各剂量动物出现--过性呼吸急促、自发活动减少、俯卧少动等症状，随剂量增加至≥320．0mg／kg时，部分动物出现濒死症状，并在给药后2～30min内死亡，死亡率随剂量的增加而增加，256．0～447．2mg／kg6个剂量组死亡率依次为0、0、10％、30％、70％、100％。未死亡动物在给药30min后逐渐恢复正常。14d观察期期间动物未见其他异常。其LD50为373．3mg／kg，95％可信限为355．6～392．0mg／kg；Ames试验结果显示，在每皿0．5—5000．0μg浓度范围内未引起4种测试菌株回复突变数增加；微核试验结果显示，dl—PHPB在23．3～210．0mg／kg范围内，各组动物MNPCEs均低于4‰；CHL细胞体外染色体畸变试验中，dl—PHPB在11．0～88．0μg／mL浓度范围内致CHL细胞染色体畸变率〈5％。结论：在本实验条件下，小鼠静脉注射dl—PHPB的LD50为373．3mg／kg，致突变性3项试验均为阴性结果。

拟无枝菌酸菌M3-1降解丙酯草醚的特性及应用初探

丙酯草醚是我国自主研制的一种新型高效油菜田除草剂。采用现代分子生物技术和微生物学传统方法从长期施用嘧啶水杨酸类除草剂的农田中富集、筛选出以丙酯草醚为唯一碳源生长的高效降解菌株M3-1,并对其最适降解条件及在土壤中的应用进行研究。结果表明:(1)经形态、生理生化和16S rDNA鉴定,M3-1属于拟无枝菌酸菌(Amycolatopsis sp.)。(2)最适温度为35℃,pH为6.0,接种量为8%,在底物(ZJ0273)浓度为100～400 mg.L.1均具有一定的降解效果,且降解率随底物浓度的增加而降低,浓度高于300 mg.L.1时,对M3-1的降解效果有较强的抑制作用。(3)最适降解条件下,水溶液中培养25 d对浓度为100 mg.L.1丙酯草醚的降解率可达63.3%。(4)M3-1在土壤中对ZJ0273有很好的去除效果,处理25 d,其降解率可达53.7%。

Up-regulation of indoleamine 2,3-dioxygenase 1(IDO1)expression and catalytic activity is associated with immunosuppression and poor prognosis in penile squamous cell carcinoma patients

Background: Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan (Trp)catabolism have been demonstrated to play an important role in tumor immunosuppression. This study examined the expression and catalytic activity of IDO1 in penilesquamous cell carcinoma (PSCC) and explored their clinical significance.Methods: IDO1 expression level, serum concentrations of Trp and kynurenine (Kyn)were examined in 114 PSCC patients by immunohistonchemistry and solid-phaseextraction-liquid chromatography-tandem mass spectrometry. The survival was analyzed using Kaplan-Meier method and the log-rank test. Hazard ratio of death was analyzed via univariate and multivariate Cox regression. Immune cell types were definedby principal component analysis. The correlativity was assessed by Pearson’s correlation analysis.Results: The expression level of IDO1 in PSCC cells was positively correlatedwith serum Kyn concentration and Kyn/Trp radio (KTR;both P < 0.001) but negatively correlated with serum Trp concentration (P = 0.001). Additionally, IDO1 upregulation in cancer cells and the increase of serum KTR were significantly associated with advanced N stage (both P < 0.001) and high pathologic grade (P = 0.008and 0.032, respectively). High expression level of IDO1 in cancer cells and serumKTR were associated with short disease-specific survival (both P < 0.001). However, besides N stage (hazard radio [HR], 6.926;95% confidence interval [CI],2.458-19.068;P < 0.001) and pathologic grade (HR, 2.194;95% CI, 1.021-4.529;P = 0.038), only serum KTR (HR, 2.780;95% CI, 1.066-7.215;P = 0.036) was anindependent predictor for PSCC prognosis. IDO1 expression was positively correlated with the expression of interferon-𝛾 (IFN𝛾, P < 0.001) and immunosuppressivemarkers (programmed cell death protein 1, cytotoxic T-lymphocyte-associated protein 4 and programmed death-ligand 1 and 2;all P < 0.05), and the infiltration ofimmune cells (including cytotoxic T lymphocytes, regulatory T lymphocytes, tumorassociated macrophages, and myeloid-derived suppressor cells;all P < 0.001) inPSCC tissues. Furthermore, the expression of IDO1 was induced by IFN𝛾 in a dosedependent manner in PSCC cells.Conclusions: IFN𝛾-induced IDO1 plays a crucial role in immunoediting andimmunosuppression in PSCC. Additionally, serum KTR, an indicator of IDO1catabolic activity, can be utilized as an independent prognostic factor for PSCC.

Characterization of catechol 1,2-dioxygenase from cell extracts of Sphingomonas xenophaga QYY

Sphingomonas xenophaga QYY, capable of growing significantly on more than ten kinds of aromatic compounds as sole carbon source, was used to study characterization of catechol 1,2-dioxygenase (C12O) in cell extracts. Characterization of the crude C12O showed that the maximum activity was obtained at 40–70°C and pH 7.8–8.8. Metal ions had different influences on the activity of crude C12O. It was suggested that strain QYY possessed an inducible and ferric-dependent C12O. Kinetic studies showed that the value of V max and K m was 0.25 μmol catechol/L/mg protein/min and 52.85 μmol/L, respectively. In addition, the partial purification of C12O was achieved by a HiTrap Q Sepharose column chromatography.

Multistep conversion of cresols by phenol hydroxylase and 2,3-dihydroxy-biphenyl 1,2-dioxygenase

A mulfistep conversion system composed of phenol hydroxylase （PHrND） and 2,3-dihydroxy-biphenyl 1,2-dioxygenase （BphCLA_4） was used to synthesize methylcatechols and semialdehydes from o- and m-cresol for the first time. Docking studies displayed by PyMOL predicted that cresols and methylcatechols could be theoretically transformed by this multistep conversion system~ High performance liquid chromatography mass spectrometry （HPLC-MS） analysis also indicated that the products formed from multistep conversion were the corresponding 3-methylcatechol, 4-methylcatechol, 2- hydroxy-3-methyl-6-oxohexa-2,4-dienoic acid （2- hydroxy-3-methyl-ODA） and 2-hydroxy-5-methyl-6-oxo- hexa-2,4-dienoic acid （2-hydroxy-5-methyl-ODA）. The optimal cell concentrations of the recombinant E. coli strain BL21 （DE3） expressing phenol hydroxylase （PHrND） and 2,3-dihydroxy-biphenyl 1,2-dioxygenase （BphCLA_4） and pH for the multistep conversion of o- and m-cresol were 4.0 （g-L-1 cell dry weight） and pH 8.0, respectively. For the first step conversion, the formation rate of 3- methylcatechol （0.29μmol·L-1·min-1·mg-1cell dry weight） from o-cresol was similarly with that ofmethylca- techols （0.28 μmol·L-1·min-1·mg-1 cell dry weight） from m-cresol by strain PHrND. For the second step conversion, strain BphCLA_4 showed higher formation rate （0.83 μmol·L-1·min-1·mg-1 cell dry weight） for 2-hydroxy-3-methyl- ODA and 2-hydroxy-5-methyl-ODA from m-cresol, which was 1.1-fold higher than that for 2-hydroxy-3-methyl- ODA （0.77 μmol·L-1·min-1·mg-1. mglcell dry weight） from ocresol. The present study suggested the potential application of the multistep conversion system for the production of chemical synthons and high-value products.

前药dl-PHPB的急性毒性及伴随毒代动力学研究

目的评价Beagle犬静脉注射丁基苯酞(dl-NBP)前体2-(α-羟基戊基)苯甲酸钾(dl-PHPB)的急性毒性反应及伴随毒代动力学。方法采用近似致死剂量法(ALD),给药剂量分别为41 mg/kg9、3 mg/kg2、10 mg/kg3、15 mg/kg。同时采用HPLC-UV方法测定血药浓度,使用DAS软件进行数据处理,和毒代动力评价,采血时间为给药后3 min1、5 min3、0 min1、h2、h4、h、6 h和8 h。结果随给药剂量的增加逐渐出现身体颤抖、头部震颤、呕吐、站立不能、后肢肌束震颤等反应,但给药后2 h基本恢复正常;315 mg/kg剂量组动物给药后6 min死亡。dl-PHPB可快速转化为dl-NBP,其AUC0-∞分别为24.8μg hr/mL、49.0μg hr/mL、76.0μg hr/mL,明显低于dl-NBP的AUC0-∞分别为200.8μg hr/mL、340.6μg hr/mL、407.1μg hr/mL。结论 Beagle犬单次静脉注射dl-PHPB的近似致死剂量范围为210 mg/kg^315 mg/kg。伴随毒代动力学研究显示dl-PHPB的毒性反应与其快速转化为dl-NBP密切相关。

酚类化合物芳环酰化反应机制的研究

三氯化铝催化下的酚类化合物芳环酰化反应,是一个傅-克反应和傅瑞斯重排反应的竟争反应。在反应初期,傅-克反应占据主导地位;在反应后期,傅瑞斯重排反应占据主导地位。另外,通过理化性质,光谱数据和化学相关法,四个新化合物的结构也分别被确定为:2-羟基-3-甲基-4-甲氧基-6-丁酰氧基苯甲酸甲酯(Ⅵ),2-丁酰氧基-3-甲基-4-甲氧基-6-羟基苯甲酸甲酯(Ⅶ),2,4-二甲氧基-3-甲基-6-丁酰氧基苯甲酸甲酯(Ⅷ),4,6-二甲氧基-2-丁酰氧基-3-甲基苯甲酸甲酯(Ⅸ)。

前药dl-PHPB在Beagle犬中反复给药毒性及伴随毒代动力学研究

目的评价I类抗脑缺血新药2-(α-羟基戊基)苯甲酸钾(dl-PHPB)在Beagle犬中反复给药30d的毒性及伴随毒代动力学。方法 Beagle犬反复给药30d,给药剂量分别为6、18、54mg/kg(分别相当于临床人体用量的3.6、10.8和32.4倍)并设溶剂对照组,停药后恢复期观察3周。同时采用HPLC-UV方法测定不同剂量下首次和末次给药的血清药物浓度。结果 54mg/kg剂量组的主要毒性反应为部分动物给药过程中出现头部颤抖,给药结束时可见血尿素氮(BUN)、肌酐(Cr)和尿pH值有所增加,相关脏器病理组织学检查未见异常;恢复期结束时上述指标均恢复正常。在6、18、54mg/kg剂量下,药后1h内dl-PHPB即完全转化为丁基苯酞(dl-NBP)。首次给药后,其活性代谢物dl-NBP的AUC0-∞分别为2.8、7.2、32.5μg.h-1.ml-1,末次给药dl-NBP的AUC0-∞分别为2.9、8.1、38.7μg.h-1.ml-1。其转化为dl-NBP的暴露比(AUC30th/AUC1st)分别为1.02、1.12和1.17。结论 Beagle犬静脉滴注dl-PHPB30d连续给药非毒性反应剂量为18mg/kg。伴随毒代动力学研究显示dl-PHPB的毒性反应与其快速转化为dl-NBP密切相关。

柔性二羧酸和双咪唑配体共同构筑的二重穿插的镍(Ⅱ)配位聚合物(英文)

本文报道了1个二重穿插的配位聚合物[Ni2(1,2-bix)2(oba)2(H2O)2],并对该化合物进行了元素分析、红外和单晶X-射线表征(1,2-bix=1,2-(二亚甲基苯)二咪唑配体,oba=4,4′-氧联苯二甲酸阴离子)。该化合物属于单斜晶系,空间群P21/n,晶胞参数a=1.475 3(5)nm,b=1.684 1(4)nm,c=2.135 6(5)nm,β=102.864(3)°,V=5.173(2)nm3,Z=4,R=0.040 5,wR=0.101 0。在该化合物中,oba和1,2-bix连接着Ni(Ⅱ)原子形成二维(4,4)网络结构。2个相邻的(4,4)网络相互穿插形成了二重穿插的二维层状结构。O-H…O氢键进一步地稳定了此层状结构。

水杨酸异戊酯合成方法的改进

研究以磷钨酸为催化剂，由水杨酸与异戊酸制备水杨酸异戊酯的工艺条件，找到最佳催化剂用量，最佳反应时间及醇酸摩尔比，并研究了带水剂对反应收率的影响。

石油烃降解菌对邻苯二酚、苯甲酸钠降解特性的研究

邻苯二酚和苯甲酸是苯类化合物代谢过程中两种常见的中间产物,也是工业废水中常见的环境污染物。为了高效去除苯类污染物,考察了高效降解石油中芳香烃组分的菌株 Acinetobacter sp. Tust-DM21 对邻苯二酚和苯甲酸钠的降解,并通过邻苯二酚 1, 2-双加氧酶(C12O)的粗酶特性和苯甲酸 1, 2-双加氧酶的酶活初步研究其代谢过程。在不含碳源无机盐培养基中,菌株 Tust-DM21 能够分别以邻苯二酚和苯甲酸钠为唯一碳源进行生长。通过改变接菌量、底物浓度、pH、温度等方面对该菌降解这两类苯类物质的特性进行研究,对 C12O 的最适 pH、温度和动力学参数以及苯甲酸 1, 2-双加氧酶的酶活进行分析。菌株对邻苯二酚的最大耐受浓度为 700 mg/L,菌株降解 600 mg/L 邻苯二酚的最佳条件为:接菌量 5%、pH6.0、温度 35℃,降解率达 92%以上。菌株可耐受 4 500 mg/L 苯甲酸钠,降解浓度为 1 500 mg/L 苯甲酸钠的最佳条件为:接菌量 3%、pH8.0、温度 35℃,降解率达 95%以上。C12O 的最适 pH 为 8.0,温度 35℃,其动力学参数为 Km=25.68 μmol/L,Vmax=0.131 mol/(mL min);苯甲酸 1, 2-双加氧酶的酶活为 3.53 U。该菌对邻苯二酚、苯甲酸钠有良好的降解效果,具有潜在的应用前景。

4-(2-氯-6-(1H-1,2,4-三唑-1-基)苯甲酰胺基)苯甲酸异丙酯的合成

[目的]开发具有全新结构的小麦全蚀病抑制剂4-(2-氯-6-(1H-1,2,4-三唑-1-基)苯甲酰胺基)苯甲酸异丙酯的合成路线。[方法]以2-氟-6-氯苯甲酸为原料,通过羧酸的酰胺化以及1,2,4-三唑的选择性取代等过程,更高效地合成4-(2-氯-6-(1H-1,2,4-三唑-1-基)苯甲酰胺基)苯甲酸异丙酯;以4-硝基苯甲酸为原料,通过酯化和还原,合成中间体4-氨基苯甲酸异丙酯。各中间体及产品通过1H NMR、13C NMR、元素分析等手段进行了结构表征和确证。[结果]所开发合成路线具有合成步骤少、中间体及产品分离容易,目标化合物的合成收率达到了62%,含量达到了98%。[结论]该合成路线为4-(2-氯-6-(1H-1,2,4-三唑-1-基)苯甲酰胺基)苯甲酸异丙酯的生理生化实验、田间试验及环境实验等样品的获得提供了有力的技术支持。

磷钨酸催化合成水杨酸异戊酯的研究

研究以磷钨酸为催化剂，由水杨酸与异戊醇制备水杨酸异戊酯的工艺条件，找到最佳催化剂用量，最佳反应时间及醇酸摩尔比，并研究了带水剂对反应收率的影响。