异黄酮碳苷类化合物(葛根素)的全合成

采用查尔酮途径全合成了一种异黄酮碳苷类化合物（葛根素）,总收率1.0%。首先4-乙基-6-叔丁基间苯二酚与2,3,4,6-四-O-苄基吡喃葡萄糖基三氟乙酰亚胺酯发生糖基化反应制得碳苷(3); 3依次经脱叔丁基和氧化制得苯乙酮类化合物(5); 5经查尔酮路线转化为葛根素,其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)确证。     

一种新型磷酸基光控保护基的合成及其应用研究

以苯硫酚为起始原料,经脱水反应、碘代反应、Suzuki-Miyaura偶联反应和氧化反应制得4-酮基-3-苯基-4H-苯并噻喃-2-甲醛(4); 4经间氯过氧苯甲酸氧化后与对甲苯磺酰肼于室温反应制得2-甲苯磺酰腙-3-苯基-4H-磺酰基苯并噻喃(6); 6经Bamford-Stevens反应合成了一种新型磷酸基光控保护基--2-重氮基-3-苯基-4H-磺酰基苯并噻喃(7),其结构经¹H NMR, ¹³C NMR和HR-MS表征。将7应用于磷酸基团的保护和光控脱保护反应中。结果表明:保护反应可在温和条件下顺利进行。紫外光谱法和荧光光谱法对光控脱保护反应的监测结果表明:光控脱保护反应迅速(≤15 min),被保护化合物脱保护收率高(≥95％)。     

新型吲唑类PARP-1抑制剂的合成及其生物活性评价

以3-甲基-2-硝基苯甲酸甲酯为起始原料,经两步反应制得中间体1H-吲唑-7-甲酸甲酯(3); 3分别与三氯氧磷、液溴和碘单质反应制得3的3-位卤代产物(4b~4d); 4d与氟试剂或氰化锌反应制得3-氟(氰基)-3(4a和4e); 4d与苯硼酸或甲基硼酸在四三苯基磷钯催化下反应制得3-甲基(苯基)-3(5a和5b);以氢化钠为碱,3, 4a~4c, 4e, 5分别与4-甲烷磺酰氧基哌啶或3-甲烷磺酰氧基四氢吡咯经缩合反应制得3的2,3-位取代产物(6a～6n); 6a～6n在甲醇中氨解,随后采用氯化氢气体脱去Boc保护基合成了14个新型吲唑类PARP-1抑制剂(7a～7n),其结构经¹H NMR和ESI-MS表征。生物活性评价结果显示,有7个目标化合物对PARP-1酶活性抑制IC₅₀低于30 nmol·L^-1,其中2-(四氢吡咯-4-基)-2H-吲唑-7-甲酰胺(7e)和3-氟-2-(四氢吡咯-4-基)-2H-吲唑-7-甲酰胺(7f)的IC₅₀分别为4.2 nmol·L^-1和4.6 nmol·L^-1。     

新型蒎酸基双酰腙类化合物的合成及其除草活性

以α-蒎烯为原料,经氧化和溴仿反应制得蒎酸(3)。在HATU作用下,3和Boc肼发生N-酰化反应得含Boc保护基的蒎酸基双酰肼(4);4脱除Boc保住基得蒎酸基双酰肼(5);5与取代苯甲醛经缩合反应合成了6个新型的蒎酸基双酰腙类化合物(6a~6f),其结构经1H NMR,13C NMR,IR,ESI-MS和元素分析表征。初步的除草活性测试表明,6a~6f在用药量为100μg·mL-1时对油菜胚根生长具有一定的抑制作用,其中蒎酸基双苯酰腙(6b)和蒎酸基双对氟苯酰腙(6d)的抑制率分别为70.1%和73.2%。     

维格列汀的合成工艺改进

L-脯氨酸经(Boc)2O保护氨基后,在氯甲酸乙酯的作用下与氨水反应生成酰胺,再脱保护基制得L-脯氨酰胺盐酸盐(4);4与氯乙酰氯酰化得(S)-N-氯乙酰基-2-氨甲酰基吡咯烷(5);5经三氯氧磷脱水得(S)-N-氯乙酰基-2-氰基吡咯烷(6);6与3-氨基-1-金刚烷醇经亲核取代反应合成了维格列汀(1)粗品。粗品与盐酸成盐后再游离制得高纯度(99.7%)的1,总收率35.5%,其结构经1H NMR和ESI-MS确证。     

合成宾达利的新方法

以邻氨基苯乙酮(2)为原料,经过连续的重氮化-还原-缩合反应序列制得3-甲基-1H-吲唑(3);3经(Boc)2O保护亚氨基后以NBS进行甲基溴代反应制得1-叔丁氧羰基-3-溴甲基-1H-吲唑(5);5与2-羟基异丁酸乙酯缩合得醚2-(1-叔丁氧羰基-1H-吲唑-3-基)甲氧基-2-甲基丙酸乙酯(6);6经HCl/乙酸乙酯溶液脱Boc保护制得关键中间体7;在叔丁醇钾存在下,7与溴苄缩合并水解合成了MCP-1抑制剂宾达利,总收率37.3%,其结构经1H NMR,13C NMR和MS确证。     

氘代AZD9291的合成

吲哚和2,4-二氯嘧啶经偶联反应制得3-(2-氯嘧啶-4-基)-1H-吲哚(1); 1与CD₃I 经取代反应制得3-(2-氯嘧啶-4-基)-1-(甲基-d₃)-吲哚(2); 2经两步亲核取代反应制得N′-(2-二甲基氨基乙基)-2-甲氧基-N′-甲基-N-{［4-(1-(甲基-d₃)吲哚-3-基)］嘧啶-2-基}-5-硝基苯-1,4-二胺(4); 4经还原反应后,与氯丙酰氯发生缩合反应合成了氘代AZD9291,总收率8.5%,其结构经¹H NMR, ¹³C NMR和ESI-MS表征。     

新型两亲性氮杂六芳基苯的合成

以5-溴-2-十二烷基嘧啶为原料,经Sonogashira偶联等反应制得1,2-双(2-十二烷基嘧啶-5-基)乙炔(4); 1-溴-4-(2-(2-(2-甲氧基乙氧基)乙氧基)乙氧基)苯(5)与双频哪醇合二硼反应制得化合物(6); 4,4′-二溴苯偶酰与1,3-二苯基丙酮经羟醛缩合反应制得四芳基环戊二烯酮衍生物(7); 化合物4与7经Diels-Alder反应制得化合物8; 8与6〖STBZ〗通过Suzuki-Miyaura偶联反应合成新型两亲性氮杂六芳基苯(9),化合物6~9为新化合物,其结构经¹H NMR, ¹³C NMR和HR-MS(MALDI-TOF)表征。     

盐酸苯达莫司汀杂质的合成

以[1-甲基-2-(4′-丁酸乙酯基)-5-氨基]-1H-苯并咪唑为原料,与氯乙醇经-N-单羟乙基化反应制得[1-甲基-2-(4′-丁酸乙酯基)-5-(2′-羟基乙基)氨基]-1H-苯并咪唑(A); A与氯化亚砜经氯化反应制得[1-甲基-2-(4′-丁酸乙酯基)-5-(2′-氯乙基)氨基]-1H-苯并咪唑(B); B在浓盐酸中经水解成盐反应合成了盐酸苯达莫司汀杂质[1-甲基-2-(4′-丁酸基)-5-(2′-氯乙基)氨基]-1H-苯并咪唑盐酸盐,总收率24.5%,纯度98.12%,其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)确证。     

新型吡唑酰腙类化合物的合成及其生物活性

以取代肼和取代乙酰乙酸乙酯为起始原料,依次经闭环、氯酰化、氧化、酯化及取代反应制得1,3-取代-5-氯-4-吡唑甲酰肼（7a, 7d, 7g和7j); 7分别与取代呋喃或噻吩甲醛经加成反应合成了12个新型的吡唑酰腙类化合物(9a~9l),其结构经¹H NMR, ¹³C NMR, IR和元素分析表征。初步的生物活性测试结果表明：在500 μg·mL^-1浓度下,部分化合物对烟草花叶病毒(TMV)具有一定的抑制活性,其中1-苯基-3-三氟甲基-5-氯-4-(2-噻吩)-腙基羰基吡唑(9k)的治疗活性、保护活性和钝化活性分别为63.6%, 85.7%和93.1%,与对照药宁南霉素(65.9%, 86.4%和97.8%)相当;在50 μg·mL^-1浓度下,部分化合物表现出一定的抑菌活性,其中1,3-二甲基-5-氯-4-(2-噻吩)-腙基羰基吡唑(9b)与1-甲基3-三氟甲基-5-氯-4-(2-噻吩)-腙基羰基吡唑(9e)对小麦赤霉病菌(Gibberella zeae)的抑制率分别为42.5%和46.8%。     

Development and validation of a capillary electrophoresis method for the characterization of protegrin IB-367.

A capillary electrophoresis (CE) method was developed to characterize protegrin IB-367, an antimicrobial peptide being developed for the treatment of oral mucositis and for other topical applications. The electrophoretic purity and levels of potential impurities/degradation products of IB-367 drug substance are determined by CE using area normalization. Electrophoresis parameters were optimized to allow optimal resolution, reproducibility and minimal analysis time. The separation and resolution between this polycationic peptide and truncated analogs determined by the CE method was much greater than those by the HPLC methods. In addition, the CE methods separates the potential impurities/degradation products from each other while the HPLC methods failed to resolve them. The CE method was validated in the aspects of accuracy, precision, linearity, range, limit of detection, limit of quantitation, specificity, system suitability and robustness. An internal standard was used for the quantitation purpose. The selection criteria of the internal standard as well as the method validation results are presented. The truncated peptide analogs were used to demonstrate the specificity of the method. These analogs were also used to evaluate the limit of quantitation of potential impurities. The relative response factors of these analogs were assessed to determine area normalization feasibility. System suitability tests were established.     

手征性硫代磷酸及其衍生物的研究(Ⅲ)——旋光活性O-乙基O-苯基硫代磷酸及其衍生物的某些反应的立体化学

本文报导了(+)-O-乙基O-苯基硫代磷酸(1R)与五氯化磷反应得到构型翻转的产物(-)-O-乙基O-苯基硫代磷酰氯(5R);5R经水解、醇解及胺解,均发生了构型翻转,并讨论了这些产物某些反应的立体化学过程。     

Mechanisms for the proton mobility-dependent gas-phase fragmentation reactions of S-alkyl cysteine sulfoxide-containing peptide ions

Mechanisms for the gas-phase fragmentation reactions of singly and multiply protonated precursor ions of the model S-alkyl cysteine sulfoxide-containing peptides GAILCGAILK, GAILCGAILR, and VTMGHFCNFGK prepared by reaction with iodomethane, iodoacetamide, iodoacetic acid, acrylamide, or 4-vinylpyridine, followed by oxidation with hydrogen peroxide, as well as peptides obtained from an S-carboxyamidomethylated and oxidized tryptic digest of bovine serum albumin, have been examined using multistage tandem mass spectrometry, hydrogen/deuterium exchange and molecular orbital calculations (at the B3LYP/6-31 + G(d,p) level of theory). Consistent with previous reports, CID-MS/MS of the S-alkyl cysteine sulfoxide-containing peptide ions resulted in the dominant "non-sequence" neutral loss of an alkyl sulfenic acid (XSOH) from the modified cysteine side chains under conditions of low proton mobility, irrespective of the alkylating reagent employed. Dissociation of uniformly deuterated precursor ions of these model peptides determined that the loss of alkyl sulfenic acid in each case occurred via a "charge-remote" five-centered cis-1,2 elimination reaction to yield a dehydroalanine-containing product ion. Similarly, the charge state dependence to the mechanisms and product ion structures for the losses of CO(2), CO(2) + H(2)O and CO(2) + CH(2)O from S-carboxymethyl cysteine sulfoxide-containing peptides, and for the losses of CH(2)CHCONH(2) and CH(2)CHC(5)H(4)N, respectively, from S-amidoethyl and S-pyridylethyl cysteine sulfoxide-containing peptide ions have also been determined. The results from these studies indicate that both the proton mobility of the peptide precursor ion and the nature of the S-alkyl substituent have a significant influence on the abundances and charge states of the product ions resulting from the various competing fragmentation pathways.     

IB-01212, a new cytotoxic cyclodepsipeptide isolated from the marine fungus Clonostachys sp. ESNA-A009

IB-01212, a new cytotoxic cyclodepsipeptide featuring C2 symmetry, was isolated from the mycelium extract of Clonostachys sp. ESNA-A009. The amino acid sequence of the compound was determined by spectroscopy techniques. The absolute configuration of the amino acids was determined by a combination of the Marfey and menthol methods. The structure, which was confirmed by comparison of the analytical data for the natural product with a sample obtained by solid-phase peptide synthesis, was revealed to be a cyclic dimer formed by two chains of L-N,N-Me2Leu-L-Ser-L-N-MeLeu-L-N-MePhe bound by the two esters formed between the carboxylic acid of the L-N-MePhe and the hydroxyl function of the L-Ser. IB-01212 is highly cytotoxic to different tumor cell lines.     

Oxidation of Two α-Hydroxy Acids by Vanadium(V)

The pathways for the oxidation of tartaric acid and citric acid by vanadium(V) in perchloric acid medium have been studied at 303K by following the formation of vanadium(IV) spectrophotometrically at 760nm. The oxidation reaction displays fractional order dependence with respect to both the -hydroxy acids concentrations as well as fractional (tartaric acid) and first order (citric acid) dependencies with respect to the perchloric acid concentration. It does not matter at all whether the ionic strength was varied or was maintained constant. The reaction rate remains essentially constant with increasing ionic strength in the tartaric acid oxidation, but decreases slightly in the citric acid case. A decrease of the dielectric constant of the reaction medium results in a rate decrease in the tartaric acid oxidation and in a rate enhancement in the citric acid reaction. The activation parameters were obtained from studies of the reactions at different temperatures (293 to 313K). Based on the experimentally determined rate laws oxidation mechanisms and theoretical rate laws were proposed.     

Synthesis of selenoxo peptides and oligoselenoxo peptides employing LiAlHSeH

Synthesis of selenoxo peptides by the treatment of N(α)-protected peptide esters with a combination of PCl(5) and LiAlHSeH is delineated. The method is simple, high-yielding, and free from racemization. Thus obtained selenoxo peptides are used as units for N-terminal chain extension through N(α)-deprotection/coupling to yield peptide-selenoxo peptide hybrids. Multiple selenation is demonstrated by conversion of two peptide bonds of tripeptides into selenoxo peptide bonds. Amino acid derived arylamides are also converted into aryl selenoamides. C(6)H(5)-CSeNH-Val-OMe 8f is obtained as single crystal, and its structure was determined through X-ray diffraction study.     

Amino acid and peptide bioconjugates of copper(II) and zinc(II) complexes with a modified N,N-bis(2-picolyl)amine ligand

Four chelating nitrogen ligands 2-5 derived from N,N-bis(2-picolyl)amine (bpa, 1) were synthesized, namely, (PyCH(2))(2)N-CH(2)-p-C(6)H(4)-CO(2)R (R = Me, 2, and R = H, 3) and (PyCH(2))(2)N-(CH(2))(n)-CO(2)H (n = 2, 4, and n = 5, 5). Amino acid conjugates 6 and 7 were formed by condensation of 3 with H-Phe-OMe and H-betaAla-OMe, respectively. Cu(II) and Zn(II) complexes of 1-7 were prepared and fully characterized. The X-ray structures of 1(Zn), 2(Zn), 4(Cu), and 7(Cu) were determined. The Zn complexes 1(Zn) and 2(Zn) as well as 7(Cu) show a distorted trigonal bipyramidal coordination environment in the solid state. An octahedral complex is observed for 4(Cu) which forms chains along the crystallographic b axis by intermolecular coordination of the carboxylic acid to the metal ion of a neighboring complex. Ligand 3 was used to prepare the peptide bioconjugate 8 (3-Ahx-Pro-Lys-Lys-Lys-Arg-Lys-Phe-NH(2)) with a nuclear localization signal (nls) heptapeptide by solid phase synthesis. Cu(II) and Zn(II) complexes of 8 were synthesized in situ and studied by FAB-MS, ESI-MS, UV/vis, and EPR (for 8(Cu)), and FAB-MS, ESI-MS, and NMR (for 8(Zn)). All spectroscopic results clearly support metal coordination to the bpa ligand in the bioconjugates 8(M), even in the presence of other potential ligands from amino acid side chains of the peptide. We suggest metal-peptide conjugates like 8(M) as artificial metallochaperones because they have the potential to deliver metal ions to specific compartments in the cell as determined by the peptide moieties.     

β-发夹多肽的全新设计和构象研究

引入跨股氨基酸队的方法进行β-发夹结构的设计,序列[R1G2T3F4W5V6d-P7S8V9N10Y11F12, β2] 中包含二个氨基酸对V6V9和F4Y11,并以d-P7S8作转角来稳定结构.多肽合成采用Fmoc/But固相合成方法.圆二色谱研究显示,β2在202 nm呈现正峰,在217.5 nm处呈负峰,为β转角和β折叠共同贡献的叠加,是典型的β-发夹结构圆二色谱特征.红外光谱研究进一步验证了圆二色谱的结果,表明β2在溶液中主要以β-发夹结构存在.     

β-发夹多肽的全新设计和构象研究

引入跨股氨基酸队的方法进行β-发夹结构的设计,序列[R1G2T3F4W5V6d-p7S8V9N10Y11F12,β2]中包含二个氨基酸对V6V9和F4Y11,并以d-p7S8作转角来稳定结构.多肽合成采用Fmoc/Bu4固相合成方法.圆二色谱研究显示,β2在202 nm呈现正峰,在217.5 nm处呈负峰,为β转角和β折叠共同贡献的叠加,是典型的β-发夹结构圆二色谱特征.红外光谱研究进一步验证了圆二色谱的结果,表明β2在溶液中主要以β-发夹结构存在.     

Investigation of in situ oxalate formation from 2,3-pyrazinedicarboxylate under hydrothermal conditions using nuclear magnetic resonance spectroscopy

We have investigated the assembly of a two-dimensional coordination polymer, Nd(2)(C(6)H(2)N(2)O(4))(2)(C(2)O(4))(H(2)O)(2), that has been prepared from the hydrothermal reaction of Nd(NO(3))(3)·6H(2)O and 2,3-pyrazinedicarboxylic acid (H(2)pzdc). In situ oxalate formation as observed in this system has been been investigated using (1)H and (13)C nuclear magnetic resonance spectroscopy, and a pathway for C(2)O(4)(2-) anion formation under hydrothermal conditions has been elucidated. The oxalate ligands found in Nd(2)(C(6)H(2)N(2)O(4))(2)(C(2)O(4))(H(2)O)(2) result from the oxidation of H(2)pzdc, which proceeds through intermediates, such as 2-pyrazinecarboxylic acid (2-pzca), 2-hydroxyacetamide, 3-amino-2-hydroxy-3-oxopropanoic acid, 2-hydroxymalonic acid, 2-oxoacetic acid (glyoxylic acid), and glycolic acid. The species are generated through a ring-opening that occurs via cleavage of the C-N bond of the pyrazine ring, followed by hydrolysis/oxidation of the resulting species.