Synthesis of

A series of 1,1'-dicinnamoylferrocenes were converted to the corresponding [3]ferrocenophane diols (4a-e) in a stereoselective manner by using samarium diiodide to effect the intramolecular coupling reaction, aldol reaction, and reduction in one-pot operation. The major reaction pathway might be derived from a samarium chelated transition state (I(A)()) having the moieties of s-cis enone and (Z)-enolate. A solid-state structure of such [3]ferrocenophane diol product showed that the cyclopentadienyl groups were in an eclipsed orientation and slightly tilted.     

多官能团分枝状化合物的合成研究：Ⅴ.多烯烃体系的合成

以六溴甲基苯为核心,季戊四醇三烯丙基醚为支化单元,采用收敛法合成了六方向,具有１８个末端烯丙基的多烯烃体系。     

Synthesis of platensimycin

In modern drug discovery, antibodies or libraries of simple synthetic organic compounds, mostly of heterocyclic origin, are favored. Natural products play an increasingly inferior role as they are considered structurally too complex, limited in quantity, and difficult to synthesize, manipulate, and derivatize. Thus it was a sensation when a Merck research group reported that classical screening of metabolites from Streptomyces platensis has unearthed a low-molecular-weight organic compound with remarkable antibiotic properties.     

Synthesis of nitrooxazoles

A reaction sequence involving halogenation and replacement of the halo substituent by a nitro group using dinitrogen tetraoxide has led to a general, convenient route to 5-nitrooxazoles. Reaction schemes employing both bromine and iodine as the halo substituent have been investigated; however, the method using iodine preceded by a mercuration step affords a better overall yield in the range of 20–50%. Both 2- and 4-nitro-oxazoles can be prepared by this latter sequence, though in lower overall yields (4–12%).     

Synthesis of mollugin

The total synthesis of mollugin, a major constituent of rubiaceous herbs, using a straightforward synthetic approach starting from 1,4-naphthoquinone via a sequence of reactions, including selective prenylation, epoxidation, reduction of the quinone moiety, acid-catalysed ring expansion, bromination, dehydration and methoxycarbonylation is presented.     

Synthesis of maradolipid

The first synthesis of maradolipid, a unique dissymmetrically 6,6'-di-O-acylated trehalose glycolipid isolated from C. elegans, is accomplished in five steps starting from trehalose in 45% overall yield. The short synthesis relies on dissymmetrization of trehalose core via regioselective acylation of a 2,3,4,2',3',4'-hexa-O-TMS trehalose 6,6'-diol derivative as a key step.     

Synthesis of glycosylcurcuminoids

Condensation of glycosylated arylaldehyde with acetylacetone-B(2)O(3) complex gave a corresponding diglycosylcurcuminoid, and a similar reaction using a mixture of arylaldehyde and glycosylarylaldehyde gave an unsymmetrical monoglycosylcurcuminoid, both as boron-complexes. The boron was removed from the complexes by heating in methanol, thus achieving the synthesis of di- and mono-glycosylcurcuminoids.     

Synthesis of pseudoiridolactones

Bicyclic δ-lactones with a carbon group at the bicyclic junction C-7a, designed as pseudoiridolactones, were synthesized from α-alkyl-α-hydroxymethylcyclopentanones via an intramolecular Horner-Wadsworth-Emmons reaction.     

Synthesis of N-cycloalkenylazoles

N-(1-Cycloalkenyl)pyrroles 3a,b, -pyrazoles 6a,b, and -imidazoles 9a,b were synthesized via elimination of benzotriazole or 5-phenyltetrazole from the corresponding 1-[1-(heterocycyl)cycloalkyl]benzotriazoles 2, 5, and 8 or 1-[1-(heterocycyl)cyclohexyl]-5-phenyltetrazole (12 and 14). Intermediates 2, 5, 8, 12 and 14 were obtained by cyclizations of dihaloalkanes with N-(benzotriazol-1-ylmethyl)heterocycles, 1-imidazol-1-ylmethyl-5-phenyltetrazole (11), or 1-pyrazol-1-ylmethyl-5-phenyltetrazole (13) in the presence of n-BuLi.     

多糖蛋白质聚合物的合成

采用大分子量,大体积的化学物质作为药物及其他生化活性物质的载体［１,２］,不但易于利用简单过滤的方法灭除细菌,而且可以提高药物与生理液体接触时的稳定性,也可以实现控制与延长药物释放的作用［３］．白蛋白是一种含量丰富的血浆蛋白,同时也是血红素,脂肪酸等...     

Synthesis of farinomalein

Farinomalein, a recently isolated maleimide from Paecilomycesfarinosus, was synthesized in two steps from a readily available γ-hydroxybutenolide.     

Gemini阳离子表面活性剂的合成及其胶束生成 Gemini阳离子表面活性剂的合成及其胶束生成

Cationic Gemini surfactants, alkanediyl-α,ω-bis(dimethyldodecylammonium bromide) have been synthesized by the following method: firstly dodecyl bromide was prepared by the reaction of dodecanol with bromic acid in the presence of strong sulfuric acid. Dodecylbromide was then reacted with N,N-tetramethyl ethane diamine(or N,N-tetramethyl hexana diamine) to prepare the title-compounds. Micellization of these Gemini surfactants was investigated using conductivity measurement. The results showed that the critical micelle concentration(cmc) of the Gemini surfactants has a much lower value compared with that of the corresponding “ monomer” . For a series of the Geminis with the same length(s) in the spacer chain, the cmc decreased with increasing the carbon number (m) in the alkyl chain. The aggregation number(N) of the micelle also drastically decreased with m. For the same value of m, the cmc varied slightly with s, which indicated that the electrostatic interaction between the ionic-groups of the “ monomer” has been naturally changed duo to a link between the two ionic-groups of the “ monomer” through a spacer. However, N was strongly decreased with s,which may be a reason of steric inhibition coming from the ionic-groups due to a link of spacer. With increasing temperature, micellization of the Gemini surfactants was slightly enhanced.     

Synthesis of mimosamycin

Mimosamycin (1) was synthesized in eight steps with an overall yield of 13% from 2-methoxy-3-methyl-1,4-benzoquinone by regioselective introduction of a chloromethyl group at C-6 and a methoxycarbonylmethyl group at C-5 and subsequent reaction of the intermediate methyl (o-(chloromethyl)phenyl)acetate derivative 16 with methylamine. Oxidation of the 5,7,8-trimethoxy-2,6-dimethyl-1, 4-dihydroisoquinoline-3(2H)-one 17 thus obtained, using cerium(IV) ammonium nitrate as a selective oxidizing agent, gave mimosamycin (1) in good overall yield.     

Synthesis of axinohydantoins

A short synthesis of the hydantoin-containing marine sponge metabolites axinohydantoins is described. A key feature of the synthesis is a putative biomimetic, intramolecular cyclization of alpha-functionalized imidazolone 5, which affords the tricyclic pyrroloazepinone framework comprising 6. In addition, the conversion of imidazolones to alpha,beta-unsaturated hydantoins is outlined and represents a new approach to these heterocyclic systems.     

Synthesis of kaempferitrin

A short synthesis of Kaempferitrin (1), a 3,7-diglycosylflavone, is reported. Key features include the synthesis of a protected form of kaempferol in which all four hydroxy groups are differentiated and the first bis-glycosylation of a dihydroxyflavone. This synthesis will allow the preparation of derivatives for further explorations into the origins of this compound's biological activity.     

Synthesis of Methylaluminoxane

Methylaluminoxane (MAO) is the most important cocatalyst of metallocene catalysts. In order to raise the hydrolysis reactions repeatability and the yield,we used the pretreated A12(SO4)3 18H2O to synthesize MAO. A few factors which influence the yield and the cocatalytic activity of MAO were discussed. The optimum condition of the reaction was obtained. The yield of MAO was raised from 40% to 49%. Synthesis of MAO: All the apparatus used was oven dried overnight and cooled under highly pure nitrogen atmosphere before use. The synthesis of MAO is carried out according to the procedure described below. 2M TMA/toluene solution was placed in a 200ml pressure balanced funnel. In a tluee necked 500ml round bottomed flask equipped with a teflon magnetic bar, the pretreated A12(SO4)3.18H2O was dispersed in dry toluene. The first neck was fitted with the pressure balanced funnel with a nitrogen outlet. The second neck was connected to nitrogen inlet. The third neck was connected to a thermowell.     

Synthesis of pyrimidinopurinophanes

Synthesis and structures of the title compounds 2a–d are described. In spite of non-parallel orientation of the two base rings, fairly large hypochromism was observed for 2a–d.     

Synthesis of thyrocalcitonin

A total synthesis of hog thyrocalcitonin is described. A protected C-terminal tridecapeptide amid (20–32) was coupled with a protected central decapeptide (10–19), and the resulting protected tricosapeptide amide (10–32) was reacted with the N-terminal protected nonapeptide (1–9). After elimination of the protective groups, a free dotriacontapeptide amide was obtained whose physical, chemical and biological behaviour was indistinguishable from that of the natural hormone.     

Synthesis of spiropyrazolines

Synthesis of a series of novel 1,3,2′-triphenyl-4-aryl spiropyrazolines [5.4′]-2′-butenolides has been accomplished in good yield by regioselective 1,3-dipolar cycloaddition of diphenylnitrilimine with (E)-3-arylidenebutenolides. X-ray crystal structure analysis of one of the products 4a confirms the structure of the product and the regiochemistry of cycloaddition. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:517–522, 1998     

Synthesis of nitropyrazolidines

Synthesis of 1, 2‐diacetyl‐4, 4‐dinitropyrazolidine 1 and results of further nitration of the 1,2‐diacetyl‐4,4‐dinitropyrazolidine are described.