Enantiospecific syntheses of deoxymannojirimycin,fagomine and 2r,5r-dihydroxymethyl-3r,4r-dihydroxypyrrolidine from D-glucose

Methyl 2-azido-3-O-benzyl-2-deoxy-α-D-mannofuranoside (4), readily available from D-glucose, is a common intermediate in the enantiospecific syntheses of deoxymannojirimycin [1,5-dideoxy-1,5-imino-D-mannitol](l), fagomine [1,2,5-trideoxy-1,5-imino-D- arabino hexitol] (2) and 2R,5R-dihydroxymethyl-3R,4R-dihydroxypyrrolidine (3); these syntheses establish the absolute configurations of (2) and (3).     

Flash photolysis of (E)-1,2-bis(1-chloro-1-phenylmethyl)cyclopropane. Generation of 1,5-diphenylpentadienyl radical and 1,5-diphenylpentadienylium cation

The 1,5-diphenylpentadienyl radical (5) is generated from (E)-1,2-bis(1-chloro-1-phenylmethyl)cyclopropane (1) via a two-photon process, either in cyclohexane or in acetonitrile as solvent. Two-laser two-color flash photolysis experiments show that excitation of the benzylic radical generated by homolysis of the first C-Cl bond leads, after ring-opening and proton loss, to the stabilized radical 5. This radical is also generated by photolysis of either (1E,3E)-5-chloro-1,5-diphenyl-1,3-pentadiene (6) or (1E,4E)-1,5-diphenyl-1,4-)pentadiene (7) via one-photon or two-photon processes, respectively. On the other hand, laser flash photolysis of 1 in acetonitrile also produces some 1,5-diphenylpentadienylium cation (10) generated via a one-photon process. Its formation can be explained as due to competitive photoheterolysis leading to a benzylic cation which thermally ring-opens and dehydrohalogenates. Species 10 is more efficiently generated by photolysis of 6 in acetonitrile and undergoes photoisomerization after laser excitation.     

Synthesis of aryl-containing isoprenoids from 1,5-dimethylcycloocta-1,5-diene

A procedure has been developed for the synthesis of Pro-Drone homo analogs from the ozonolysis products of 1,5-dimethylcycloocta-1,5-diene and 1,5-dimethylcyclooctene.     

Chlorination of 1,5-dimethylpyrazole

The chlorination of 1,5-dimethylpyrazole by gaseous chlorine in acetic acid in the presence of sodium acetate affords 1-methyl-3,4-dichloro-5-(dichloromethyl)pyrazole, which is subsequently converted to the 5-(trichloromethyl) derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 352–354, March, 1990.     

Stereoselective synthesis of chiral 3,4,5-trisubstituted 1,5-dihydropyrrol-2-ones from azadienes

A new access to enantiopure 3-phthalimido-4-amino-5-(1-hydroxyalkyl) 1,5-dihydropyrrol-2-ones has been developed from 1,3-azadienes. Stereoselective Lewis acid catalyzed addition of a cyano group to an azadiene, followed by intramolecular ring closure, in a four-step one-pot synthesis, results in the formation of γ-lactams in satisfactory yields.     

2-甲基-1,5-苯并硫氮杂的基态和激发态反应的研究 I: 2-甲基-1,5-苯并硫氮杂-4(5H)-酮的卤化和亲核取代反应

2-甲基-1,5-苯并硫氮杂-4(5H)-酮(1a)与不同的氯化试剂-五氯化磷、三氯氧磷和氯化砜在不同的条件下氯化,可分别生成:2-甲基-4-氯-1,5-苯并硫氮杂(2a)、2-氯-4-甲基-1,5-苯并硫氮杂(3a)、2-二氯甲基苯并噻唑(5)、2-三氯甲基苯并噻唑(6)和2-甲基-1,5-苯并硫氮杂-4(5H)-酮盐酸盐(4).2-甲基-4-氯-1,5-苯并硫氮杂与醇钠反应生成相应的2-甲基-4-烷氧基-1,5-苯并硫氮杂外,还可以分离到它的2,4-异构体,2-烷氧基-4-甲基-1,5-苯并硫氮杂.产物的结构均经元素分析、红外光谱、^1H和^1^3C核磁共振谱和质谱鉴定.     

Synthesis of 2-acyl-3-methylthiofurans from 3-methylthio-2-pentene-1,5-dione enolates

2-Acyl-3-methylthiofurans 3 are obtained in fair yields from 3-methylthio-2-pentene-1,5-dione enolates 1 by reaction with iodine. In a similar reaction 1-phenyl-3-methylthio-4-nitro-2-buten-1-one gave 3-methylthio-2-nitro-5-phenylfuran 11. In the crystalline state the 2-benzoyl-3-methylthio-5-phenylfuran 3b showed a non-bonded sulfur-oxygen interaction as inferred from an X-ray diffraction determination, with a S····O distance of 2.871(5)Å.     

含1,2,3-三氮唑结构的1,5-苯并硫氮杂[艹卓]的合成及其抑真菌活性

设计合成了三类含1,2,3-三氮唑结构的1,5-苯并硫氮杂[艹卓]化合物3-(1H-1,2,3-三氮唑)-4-芳基-2,5-二氢-1,5-苯并硫氮杂[艹卓](5a^5f)、3-(2H-1,2,3-三氮唑)-4-芳基-2,3-二氢-1,5-苯并硫氮杂[艹卓](6a^6f)和3-(1H-1,2,3-三氮唑)-4-芳基-2,3,4,5-四氢-1,5-苯并硫氮杂[艹卓](7a^7f).研究了中间体及目标产物的合成条件,分离出其中两个副产物并进行了结构确定.目标产物的抑真菌活性测试表明,化合物5a^5f对真菌具有良好的抑制作用,对新生隐球菌的抑制效果尤为突出.初步抑真菌构效关系研究表明, 1H-1,2,3-三氮唑环和C=C双键是化合物5a^5f抑真菌活性的关键官能团.     

Five-membered 2,3-dioxo heterocycles. 2. Synthesis and [1,5]-sigmatropic rearrangement of 4-acyl-3-diphenylmethoxy-1,5-diphenyl-2,5-dihydropyrrol-2-ones

4-Acyl-1,5-diphenyltetrahydropyrrole-2,3-diones react with diphenyldiazomethane to give O-alkylation products, which upon heating undergo [1,5]-sigmatropic suprasurface rearrangement to form 4-[methyl- and 4-[-aryl(diphenylmethoxy)-methylene]-1,5-diphenyltetrahydropyrrole-2,3-diones.See [1] for Communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii. No. 5, pp. 625–628, May, 1987.     

13,17,53,57-Tetraphenyl-13,17,53,57-tetrathio-3,7-dithia-1,5(1,5)-di(1,5-diaza-3,7-diphosphacyclooctana)-2,4,6,8(1,4)-tetrabenzenacyclooctaphane with an unusual conical-like conformation

1³,1⁷,5³,5⁷-tetraphenyl-1³,1⁷,5³,5⁷-tetrathio-3,7-dithia-1,5(1,5)-di(1,5-diaza-3,7-diphosphacyclooctana)-2,4,6,8(1,4)-tetrabenzenacyclooctaphane 2b was obtained by sulfurization of the corresponding macrocyclic tetraphosphine 1b. The structure of the inclusion complex of tetrasulfide 2b with DMF was investigated by the X-ray crystal structure analysis. A novel for this type of cyclophanes and relatively rare conical-like conformation of the macrocycle was found. A methyl group from one of the solvating DMF molecules penetrates the macrocyclic cavity of 2b from the side of the wider rim. According to quantum-chemical simulations, this may be the reason of the unusual conical conformation of 2b because the cavity of the macrocycles of this type is highly flexible. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Zur Konstitution des 1,5-Diphenylcarbazonato—Diphenylbor-Chelates — ein chemischer Beweis

Further development of the reagent 1,5-diphenylcarbazone (1) with regard to higher sensitivity and better selectivity requires the knowledge of the constitution of the chelates. For this purpose 1-methyl-1,5-diphenylcarbazonato—diphenylboron was synthesized, which can only be formed from the enol-form of the so far unknown unsymmetrical 1-methyl-1,5-diphenyl-carbazone6. From the various compounds which contain the hydrazo part of 1,5-diphenylcarbazone (1). only picolinic acid phenylhydrazide14 forms a boron chelate, from which it can be concluded that the boron atom is coordinated to the N-5 of the azo group (formula5).     

Antifilarial and antimalarial agents. Basically substituted 10-aminobenzo[b] [1,5] naphthyridines, 10-Aminobenzo[b] [1,5] naphthyridine N-Oxides,and 8-Amino-1,5-naphthyridines

Various 2-alkoxy 7-chloro-10-[[[(dialkylamino)alkyl]amino]]benzo[b][1,5]naphthyridines (XI) and N-oxides (XV, XVII, XVIII, XXII), 4-[(2-alkoxy-7-chlorobenzo[b][1,5]naphthyridin-10-yl)-amino]-α-(diethylamino)-o-cresol derivatives (XII-XIV, XXI) and N-oxides (XIX, XX, XXV), 2-butoxy-8-[[[(dialkylamino)alkyl]amino]]-1,5-naphthyridines (XXVIa and b), and 2-butoxy-8–[[3-[(diethylamino)methyl]-p-anisidino]]-1,5-naphthyridine (XXVII) were synthesized for antifilarial and antimalarial evaluation. The compounds were obtained in 13–91% yield by the condensation of 2-alkoxy-7,10-dichlorobenzo[b][1,5]naphthyridines, 2-alkoxy-7,10-dichlorobenzo[b][1,5]naphthyridine 5-oxides, and 2-butoxy-8-chloro-1,5-naphthyridine with the appropriate diamine in phenol, or by perbenzoic acid oxidation of the parent 10-amino-7-chlorobenzo-[b][1,5] naphthyridines in chloroform. Among them, eight compounds killed adult Litomosoides carinii in gerbils when administered in daily gavage doses of 25–400 mg./kg. for 5 days. Azacrine 5-oxide (XVII), the most active compound, was equipotent with amodiaquine (1a), azacrine (IX), and quinacrine 10-oxide (VI). Twelve substances were active orally against Plasmodium berghei in mice at doses ranging from 3.8–155 mg./kg./day for 6 days. 7-Chloro-10-[[-3-[(diethylamino)-methyl]-p-anisidino]]-2-methoxybenzo[b][1,5]naphthyridine 5-oxide dihydrochloride (XX) was approximately 12 times as potent as quinine against P. berghei, but was highly cross-resistant with chloroquine (IV). Structure-activity relationships are discussed.     

The configuration and solid state conformation of 3,7-dihydroxy-1,5-bis(p-bromophenyl)octahydro-1,5-diazocine

The crystal structure of 3,7-dihydroxy-1,5-bis(p-brornophenyl)octahydro-1,5-diazocine ( 4 ) has been determined from the three dimensional x-ray diffraction data. This infers a similar structure for 3,7-dihydroxy-1,5-diphenyloetahydro-1,5-diazocine ( 1 ). The molecules are in a twist crown conformation and the configuration of the hydroxyl groups on the 3,7-positions is cis.     

Tautomerism of 1,5-dibenzazolylformazans

The structures of new symmetrical and asymmetrical 1,5-dibenzazolylformazans were investigated by IR and electronic spectroscopy. It is shown that 1,5-dibenzimidazolylformazans, regardless of the substituent in the 3 position (methyl, phenyl), display the presence of the tautomeric imino form in solutions. 1,5-Dibenzothiazolylformazans display a high tendency to form chelate forms. The stability of the chelate increases on passing from the 3-methyl to the 3-phenyl derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 699–701, May, 1973.     

Einfache Synthesen Von 1,5-Didesoxy-1,5-Imino-D-Glucit (1-Desoxynojirimycin) Und 1,6-Didesoxy-1,6-Imino-D-Glucit Aus D-Glucofuranurono-6,3-Lacton

ABSTRACT

1,5-Dideoxy-1,5-imino-D-glucitol (1-deoxynojirimycin) and 1,6-dideoxy-1,6-imino-D-glucitol were synthesised by simple sequences in seven and six steps, respectively, from D-glucofuranurono-6,3-lactone. Attempts to improve the yield of the crucial regio- and stereospecific introduction of azide into position 5 of suitable derivatives of this substrate are described.     

Enantioselective synthesis of 1,5-anti- and 1,5-syn-diols using a highly diastereoselective one-pot double allylboration reaction sequence

Highly diastereo- and enantioselective syntheses of 1,5-disubstituted (E)-1,5-anti-pent-2-endiols 1 and (Z)-1,5-syn-pent-2-endiols 2 have been achieved via the one-pot coupling of two different aldehydes with either (E)-gamma-(1,3,2-dioxaborinanyl)-allyl]diisopinocampheylborane (4) or (E)-gamma-(4,4,5,5-tetraphenyl-1,3,2-dioxaborolanyl)allyl]diisopinocampheylborane (11), respectively. The indicated diols 1 and 2 are obtained in 63-95% yield with 89-96% ee and >/=20:1 diastereoselectivity in all cases. The bifunctional gamma-boryl-substituted allylborane reagents 4 and 11 were generated in situ by the hydroboration of allenes 3 and 10 with diisopinocampheylborane. The keys to the success of this method are the excellent stereocontrol in the allylboration step leading to 5 and the corresponding substituted methallylboronate derived from 11, the stereospecificity of the subsequent allylboration reaction of the substituted methallylboronate intermediates, and the ability of the diol auxiliary to induce equatorial or axial placement of the substituent alpha to boron in transition states 7 and 8.     

The synthesis of certain 8-cyano-2,4-disubstituted-imidazo[1,5-a] pyrimidines

A number of imidazo[1,5-a]pyrimidine-8-carboxamides were synthesized by reacting various β-dicarbonyl compounds with 5(4)-aminoimidazole-4(5)carboxamide (AICA, 1 ), the non-ribosylated form of AICAR, a key intermediate in the metabolic pathway of purine biosynthesis. Cyclization of 1 with ethylacetoacetate yielded 2-methylimidazo[1,5-a]pyrimidin-1H-4-one-8-carboxamide ( 2 ). The treatment of 2 with phosphorus oxychloride gave 4-chloro-8-cyano-2-methylimidazo[1,5-a]pyrimidine ( 3 ). Various nucleophiles displaced the 4-chloro substituent of 3 under mild conditions. However, the 4-methylthio group of 8-cyano-2-methyl-4-methylthioimidazo[1,5-a)pyrimidine ( 8a ) was also displaced under very mild conditions. Even more strangely, the 4-diethylamino group of 8-cyano-4-diethylamino-2-methylimidazo[1,5-a]pyrimidine ( 5a ) was displaced by ammonia to give 4-amino-8-cyano-2-methylimidazo[1,5-a]pyrimidine ( 7 ).     

Pyrazolo[1,5-d]triazines-1,2,4. II étude des pyrazolo[1,5-d]triazinones,des pyrazolo[1,5-d]triazinediones et des pyrazolo[1,5-d]triazinethiones

The synthesis of 1,2-dihydro-l-oxopyrazolo[1,5-d]-1,2,4-triaxine was achieved by rerrangment of 2-(5-pyrazolyl)-1,3,4-oxadiazole under alkaline condition. The cyclization of the N-carbethoxyhydrazone of the pyrazole-5-carboxaldehyde gave the 3,4-dihydro-4-oxopyrazolo[1,5-d]1,2,4-triazine. Electrophilic substitutions of the l-pyrazolotriazinome were made either on the lactam nitrogen with methylsulfate, benzylchloride and monochloracetic axid or on the pyrazole ring with bromine. The synthesis of pyrazolo[1,5-d]-1,2,4-triazine was made from teh l-pyrazolotrizinone via the l-pyrazolotrizinone. The methylation of l-pyrazolotrizinone and 8-bromo-l-pyrazolotrizinone afforded N-and S-methyl derivatives. The sysnthesis of 1,2,3,4-tetrahydropyrazolo[1,5-d]-1,2,4-triazine-1,4-diones was axhived by cyclising N-carbethoxyhydrazides of pyrrole-5-carboxylic acid. The structures of the derivatives were determined by ¹H-nmr.     

Polyimides from 1,5-bis(4-amino-2-trifluoromethylphenoxy)naphthalene and aromatic tetracarboxylic dianhydrides

A new trifluoromethylated bis(ether amine), 1,5-bis(4-amino-2-trifluoromethylphenoxy)naphthalene, was synthesized in two steps starting from 1,5-dihydroxynaphthalene and 2-chloro-5-nitrobenzotrifluoride via nucleophilic aromatic substitution and catalytic reduction. A series of novel fluorinated polyimides with moderate to high molecular weights were synthesized from the diamine with various aromatic tetracarboxylic dianhydrides using a conventional two-stage process. All polyimides could afford flexible and tough films and most of them were soluble in strong polar solvents such as N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc). The polyimides showed glass-transition temperatures (T_g) in the range of 253-315 °C (by DSC) and softening temperatures (T_s) in the range of 250-300 °C (by TMA). Decomposition temperatures for 5% weight loss all occurred above 500 °C in both air and nitrogen atmospheres. The dielectric constants of these polymers ranged from 3.17 to 3.64 at 1 MHz. The properties of these fluorinated polyimides were also compared with those of polyimides prepared from 1,5-bis(4-aminophenoxy)naphthalene with the same dianhydrides.     

Facile Preparation of 3,7-Diazabicyclo[3.3.0]octane and 3,7,10-Triheterocyclic [3.3.3]Propellane Ring Systems from 1,5-Diazacyclooctane 3,7-Derivatives(1)

The cyclodimerization of p-toluenesulfonamide and 3-chloro-2-(chloromethyl)-1-propene to prepare N,N'-bis(p-toluenesulfonyl)-3,7-bis(methylene)-1,5-diazacyclooctane (1a) and its ozonation to the corresponding 3,7-dione 2a are reported. Unusual transannular cyclizations initiated by lithium aluminum hydride treatment or bromination of 1a and oxidative coupling of the dioxime derived from 2a are described. These reactions lead, respectively, to the following derivatives of the little-studied 3,7-diazabicyclo[3.3.0]octane ring system: 1,5-dimethyl-3,7-diazabicyclo[3.3.0]octane (5), N,N'-bis(p-toluenesulfonyl)-1,5-bis(bromomethyl)-3,7-diazabicyclo[3.3.0]octane (8), and N,N'-bis(p-toluenesulfonyl)-1,5-dinitro-3,7-diazabicyclo[3.3.0]octane, (12). Acid-catalyzed hydration of 1a, in contrast, gives the expected 5-methyl-3,7-diazabicyclo[3.3.1]nonan-1-ol (10). Reaction of the dibromide 8 with the nucleophiles, sodium sulfide, sodium oxide, and sodium p-toluenesulfonamide conveniently delivers the corresponding novel 3,7,10-triheterocyclic [3.3.3]propellanes.