Zearalenone Mimics: Synthesis of (E)-6-(1-Alkenyl)-substituted β-Resorcylic Acid Esters

Two versatile strategies for the synthesis of mimics of the Fusarium mycotoxin zearalenone (1) have been developed. Optimized preparation of (E)-6-(1-alkenyl) substituted β-resorcylic acid esters was realized via ortho-directed lithiation of variable substrates combined with allylation/isomerization or via formylation/Schlosser–Wittig olefination using different protective group patterns. Spontaneous decarboxylation of (E)-6-(1-alkenyl) substituted β-resorcylic acids indicated the influence of this substituent on the chemical behavior of these compounds. These mimics were already used for the development of optimized standard protocols for the synthesis of phase II metabolites of ZEN (glucosides, glucuronides), and further applications (i.e., sulfate conjugates) are still under investigation.

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炔雌醚-6-酮-(O-羧甲基)肟和炔雌醇-6-酮-(O-羧甲基)肟的合成

为了研究长效口服避孕药复方炔雌醚的作用机理,我们采用放射免疫测定法,测定服药者血中炔雌醚(17α-乙炔雌二醇-3-环戊醚)及其代谢产物炔雌醇(17α-乙炔雌二醇)的浓度,以观察它们的动态变化规律.甾体化合物的分子量较小,本身没有抗原性,所以须先制备半抗原,然后再与大分子载体,如牛血清白蛋白结合,方能使动物免疫而产生抗血清.目前甾体雌激素的半抗原多采用6-(O-羧甲基)肟衍生物.通常先用铬酐-乙酸氧化雌激素,引入6-酮基,再制成肟衍生物.但是铬酐-乙酸的氧化产物甚为复杂,得率亦低.     

Synthesis and structure of η6-(biphenyl)-η5- (cyclopentadienyl)iron(II) hexaflourophosphates

A series of η⁶-(biphenyl)-η⁵-(cyclopentadienyl)iron(II) hexafluorophosphates have been prepared. Demethylation occured during the synthesis of the 2′-OMe derivatives to yield the correspoding 2′-OH product. The mechanism of this process is discussed. In all cases the complexation involved the unsubstituted phenyl ring. From ¹³C NMR data, values of Hammett resonance parameters σ_R, were calculated which show that the [CpfeC₆H₅]⁺ group behaves as an electron-withdrawing substituent comparable in strength to the cyano group. Approximate values of the biphenyl interplanar angle (θ) were obtained. θ appeared to be significantly lower when electron-releasing substituents were present. ⁵⁷ Fe Mössbauer data support the strong electron acceptor properties of the [CpFe⁺C₆H₅] moiety. In particular the quadrupole splitting (QS) shows a marked increase for the 4-OMe derivative relative to the unsubstituted comples. This is in direct contrast to the aryl ferrocenes. Here, the ferrocenyl and OMe substituents are electronically and so there is no (QS) enhancement.     

Lowest energy electronic transition in aqueous Cl(-) salts: Cl(-) → (H2O)6 charge transfer transition

We use UV resonance Raman spectroscopy to probe the lowest energy allowed electronic transitions of aqueous solutions containing Cl(-) salts. We show that the waters hydrating the Cl(-) are involved in charge transfer transitions that transfer electron density from Cl(-) to the water molecules. These charge transfer transitions cause significant change in the H-O-H bond angle in the excited state, which results in a strong enhancement of the preresonance Raman intensity of the water bending modes. Our work gives the first insight into the lowest allowed electronic transition of hydrated Cl(-).     

(η6-1,2,3-Trimethoxybenzene) tricarbonylchromium complex: regioselectivity of the deprotonation

Deprotonation of (h⁶-1,2,3-trimethoxybenzene)tricarbonyl chromium with n-BuLi occurs mainly at the C4 carbon while the use of LiTMP gives predominantly the C5-substituted product.     

4-(6-甲氧基-8-喹啉偶氮)-间苯二酚与Ni(Ⅱ)的显色反应

研究了4-(6-甲氧基-8-喹啉偶氮)-间苯二酚(MQAR)与Ni(Ⅱ)的显色反应。确立了Ni(Ⅱ)与MQAR显色反应的条件,配合物的最大吸收波长为570nm,对比度为98nm,镍含量在0.2-1.6mg·L-1范围内服从比耳定律,表观摩尔吸光系数为2.63×104L·mol-1·cm-1,表观稳定常数为1.26×10(10),Sandell灵敏度为2.17×10-3μg·cm-2。用于人发和血清中镍的测定,取得了满意的结果。     

(3S,6S)-及(3S,6R)-3-苄氧甲基-6-甲基-吗啉-2,5-二酮的 制备及其晶体结构

以2-溴丙酸和N-叔丁氧羰基-O-苄基-L-丝氨酸为起始试剂首先制得N-(2-溴丙基)-O-苄基-L-丝氨酸(BPBS), 在N,N-二甲基甲酰胺(DMF)/三乙胺(Et3N)溶剂中80 ℃经9 h后BPBS发生分子内环化反应生成(3S,6S)-3-苄氧甲基-6-甲 基-吗啉-2,5-二酮[(3S,6S)-BMMD]及(3S,6R)-BMMD共存体, 产率70%. 将所制得的共存体以乙酸乙酯为重结晶溶剂, 采用微分重结晶法, 经4次“溶解-部分重结晶”操作循环制得两种纯光学构型的(3S,6S)-BMMD和(3S,6R)-BMMD. 将两种光学纯双手性中心的BMMD分别溶于乙酸乙酯, 室温下培养得(3S,6S)-BMMD和(3S,6R)-BMMD的单晶体, 以X射线衍射法测定上述两种BMMD的分子结构.     

YOUJI HUAXUE(Organic Chemistry)1989(1-6) Author Index

(539)566YOUJI HUAXUE(Organie Chemistry)1 989(1一6)Author IndexBAI Guang~Chai 41 Balavoine,G.445 Bandy,J.A.422Bosso,C.141,146Cambon,A.141,146CAO Zhe一Yu 543CAO Zheng-Bai 337CHEN Chao-Huan 343CHEN Hen于Chang 49CHEN Jja一Wei 80,353,521ChEN Ke一Qians,337CHENL卜Ya 193,300CHEN Ling-Ling 543CHEN Mao一Qi 355CHEN Min一Dong 321CHEN Qin于Hua 156CHEN Shu~Hua 266CHEN Tong-Qian 431CHEN Wei一Xin 271CHEN Wen~Kan 328CH卫N Yao一Huan 343CHEN YiweZhao 132CHEN YO…     

[4 + 6]-cycloaddition von 1,3-butadien an hexacarbonyl-μ-η6:6-heptafulvalen-dichrom(0)

The thermal reaction of heptafulvalene (I) with [Cr(CO)₃(CH₃CH)₃] (II) gives the hexacarbonyl-η^6:6-heptafulvalenedichromium(0) complex (III). UV irradiation of complex III in THF solution, with 1,3-butadiene (IV) in successive [4 + 6]-cycloadditions and decomplexations gives the complexes tricarbonyl-η⁶-11-(2,4,6-cycloheptatrien-1-ylidene)bicyclo[4.4.1]undeca-2,4,8-trine-chromium(0) (V) and tricarbonyl-η⁶-bi(bicyclo[4.4.1]undeca-2,4,8-trien-11-ylidene)-chromium(0) (VI). On warming, VI looses the bi(bicyclo[4.4.1]undeca-2,4,8-trien-11-ylidene) hydrocarbon ligand (VII). The reaction of VII with [Mo(CO)₃(diglyme)] (VIII) gives the tricarbonyl-η⁶-bi(bicyclo[4.4.1]undeca-2,4,8-trien-11-ylidene)molybdenum(0) complex (IX). The compounds III, V–VII and IX were characterized by IR and NMR spectra (¹H, ¹³C) and by C,H elemental analysis.     

3-氨基-6-(2-(4-吡啶基)乙烯基)-9-丁基咔唑的合成及性质

通过咔唑的烷基化、硝化、碘化、Heck偶联反应、水合肼还原,设计合成了一种新型D-π-A结构的咔唑衍生物3-氨基-6-(2-(4-吡啶基)乙烯基)-9-丁基咔唑(L)。化合物的结构通过红外、核磁氢谱、碳谱和质谱等技术手段的表征。通过测定在不同溶剂中的紫外、荧光、循环伏安和理论计算,初步研究了化合物L的光学、电化学性质和电子结构。研究结果表明,化合物L的紫外吸收光谱和荧光发射光谱随着溶剂极性的增加发生不同程度的红移。     

Oxidation of theexo- andendo-phenylcyclohexadienyl iron complexes Fe(η5-6-PhC6H6) (η5- C5H5)

The roe of oxidatively induced homolyhc scission a the C(sp³)-H bonds in the iron phenykychhexadienyl complexes Fe(⁵-6-PhC₆H₆)(⁵-C₅H₅) (1) depends on the spatial orientation of the Ph substitutent. In the case of the (1 _endo ⁺) radical cation this process, resulting in the cationic biphenyl complex (Fe(⁶ -C₆H₅C₆H₅)(⁵-C₅H₅)]⁺ (2 ⁺), is fast and proceeds for several minutes. In the case of the more stable radical cation (1 _exo ⁺) the formation of 2⁺ is slow and takes tens minutes to complete.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1698–1700, July, 1996.     

4-(6-甲氧基-8-喹啉偶氮)-邻苯二酚分光光度法测定大米中的铜(Ⅱ)

4-(6-甲氧基-8-喹啉偶氮)-邻苯二酚(MQAPC)与铜(Ⅱ)可生成稳定的配合物,配合物的最大吸收波长为580 nm,表观摩尔吸光系数为7.64×104L/(mol.cm),据此用分光光度法测定大米中的铜(Ⅱ),铜(Ⅱ)的浓度在0.1~1.0μg/mL内与吸光度成线性关系。该方法测定结果的相对标准偏差为3.4%,加标回收率为100%~104%。     

A Practical Synthesis of (S)-(+)-2-(6-methoxyl-2-naphthyl) propionic Acid

a-Arylpropionic acids are an important class of non-steroidal anti-inflammatory agents1,2. The therapeutic efficacy of this class of drugs is well demonstrated by the introduction and extensive use of more than a dozen compounds exemplified by ibuprofen, naproxen, ketoprofen and flurbiprofen etc. However, in recent years the use of enantiomerical pure drugs in chemotherapy is becoming almost mandatory for enhancing specificity of drug action and reducing the toxicity. This awareness led to …     

银盐法合成6-(4-卤代苯基)-3(2H)-哒嗪酮葡萄糖苷

Four pyridazinone gluosodes 4 were synthesized by Koenig' s-Knorr reaction of 6-(4-halophenyl)-3 (2H)-pyridazinone silver salt 2 with bromoaeetylglueose 3. Treatment of 4 with dry ammonia at 0 ～ - 5 ℃ effeeted a removal of the acetyl protecting groups to yield compounds 5. When the substituent on the benaene ring was F-or Cl-,O-glueoside was synthesized prineipaUy. However, when the substituent was Br-or I-, N-glueoside was mainly obtained. Their struetures were confirmed by ^1H NMR, IR and elemental analysis.     

Synthesis of an antimetastatic tetrasaccharide β-D-Gal-(1→4)-β-d-GlcpNAc-(1→6)-α-D-Manp-(1→6)-β-D-Manp-OMe

An antimetastatic tetrasaccharide T₁,β-D-Gal-（1→4）-β-D-GlcpNAc-（1→6）-α-D-Manp-（1→6）-β-D-Manp-OMe,was synthesized with two approaches.The first approach was a conventional method employing thioglycoside and Koenigs-Knorr glycosylation reaction in 24%overall yield.The second one was a novel route through the azidoiodo-glycosylation strategy by using 2-iodo-2-deoxylactosyl azide as the donor in 36%overall yield.     

Photophysical Properties of 4′-(p-aminophenyl)-2,2′:6′,2′′-terpyridine

Spectral and photophysical investigations of 4′-(p-aminophenyl)-2,2′:6′,2′′-terpyridine (APT) have been performed in various solvents with different polarity and hydrogen-bonding ability.The emission spectra of APT are found to exhibit dual fluorescence in polar solvents, which attributes to the local excited and intramolecular charge transfer states, respectively. The two-state model is proven out for APT in polar solvent by the time-correlated single photon counting emission decay measurement. Interestingly, the linear relationships of different emission maxima and solvent polarity parameter are found for APT in protic and aprotic solvents, because of the hydrogen bond formation between APT and alcohols at the amino nitrogen N25. Furthermore, the effects of the complexation of the metal ion with tpy group of APT and the hydrogen bond formation between APT with methanol at the terpyridinenitrogen N4—N8—N14 are also presented. The appearance of new long-wave absorption and fluorescence bands indicates that a new ground state of the complexes is formed.     

核酸的利用(二) N~6-(3-甲基-2-丁烯基)腺苷的合成

近些年来,随着核酸化学的发展,已经设计并合成了一系列对恶性肿瘤、病毒以及心血管疾病有较好疗效的核酸类药物。已有报告 N~6-(3-甲基-2-丁烯基)腺苷能抑制艾氏腹水癌和淋巴白血病 L1210的生长。初步临床试验证明,它对患急性骨髓性白血病的儿童产生血象的和临床的缓解作用,而其对肝脏的损害是可逆性的。无产阶级文化大革命以来,工业战线广大职工遵照毛主席关于开展综合利用的指示,广泛地开展了对发酵工业副产物核糖核酸的综合利用的研究工作。在这些工作的推动下,我们也开始把抗肿瘤药物的研究与核酸的综合利用结合起来,把寻找新药的研究和试制已知药物结合起来。我们七四届工农兵学员在毕业     

氮肥增效剂——6-氯-2-(三氯甲基)吡啶

肥料是植物的粮食。增施肥料是提高作物产量的重要措施之一。据测定,化学氮肥施入田间后,仅有30—50%被作物吸收利用,尚有一部分由于受土壤中硝化细菌的作用,使氨态氮转化成硝酸态氮和亚硝酸态氮,不易被作物吸收而流失,也有部分硝酸态氮在缺氧条件下被反硝化细菌作用,变成氮气而逸掉。氮肥增效剂是一种硝化抑制剂,和氮肥配合共同施于田间,可以有效地抑制硝化细菌对氨态氮的硝化     

Asymmetric Synthesis of (-)-(2R,3R,6S)-Irnigaine

Introduction　　Asarelativelynewmemberofnaturalalkaloidswith2 ,6 disubstituted 3 piperidinolskeleton ,irnigaine 1wasisolatedfromthetubersofArisarumVulgare (Araceae)in1995byMelhaouiandBode .1Itsstructureandrelativeconfigurationswereelucidatedby1HNMRstudiesandtheabsoluteconfigurationwasproposedonthebasisofitsopti calrotation .1Soonafterthen ,Meyerandhisco workersreportedthefirstsynthesisof (- ) (2R ,3R ,6S) irni gaineandtheconfigurationconfirmation .Althoughtheirsynthesisroutewasshortan…     

First Total Synthesis of (-)-4-O-(6'-hydroxy-7'(9')-dehydro-6',7'-dihydrogeranyl)-coniferyl Alcohol

SomeLigulariaspecieshavelongbeenusedasfolkremediesduetotheirantibiotic,antiphlogisticandantitumoracti.ities'.Compound1',anovelconiferylalcoho1,wasisolatedfromLigulariaduciformis(Compsitae)alongwiththreenewstructuressuchas2,3,4(Figure1).Thegeometricalstructureof1,deterndnedbyspectroscopictechniques,correspondedto4-o-(6'-hydroxy-7'(9')-dehydro-6coniferylalcohol.ButitsabsoluteconfigurationatC-6'hasnotyetbeendetermined.Hereinwereportthetotalsynthesisof(6'S)-(-)-lfromgeraniol5throughninesteps(Sc…