- Facile o-quinodimethane formation from benzocyclobutenes triggered by the Staudinger reaction at ambient temperature
-
Electron-donating iminophosphoranes were found to significantly enhance 4π-ring opening of benzocyclobutenes to generate o-quinodimethanes at 20-25 °C. These iminophosphorane benzocyclobutenes can be conveniently generated from azide benzocyclobutenes and phosphines via the Staudinger reaction. Thus, Staudinger reaction-triggered sequential molecular transformations of the azide benzocyclobutenes have been established via o-quinodimethanes at ambient temperature, which is expected to exhibit potential for a wide range of applications.
- Kohyama, Aki,Koresawa, Eri,Tsuge, Kiyoshi,Matsuya, Yuji
-
p. 6205 - 6208
(2019/06/07)
-
- Ormetoprim synthesis method
-
The invention provides an ormetoprim synthesis method. The method includes steps: subjecting p-cresol and dimethyl carbonate to phenolic hydroxymethylation to obtain a compound I; subjecting the compound I and potassium bromide to bromination reaction under an acetic anhydride-nitric acid system to obtain a compound II; taking cuprous chloride as a catalyst, and subjecting the compound II and sodium methylate methanol solution to methoxylation reaction to obtain a compound III; subjecting the compound III and a VHA reagent to formylation reaction to obtain a compound IV; subjecting the compound IV to reaction with sodium methylate and acrylonitrile methanol solution to obtain a compound V; after the compound V is subjected to alkali isomerization to obtain a vinyl ether structure, subjecting to addition reaction with methyl alcohol and direct condensation and cyclization with guanidine to finally obtain a compound VI which is a final product namely ormetoprim. Defects in the prior art are overcome, and the provided ormetoprim synthesis method has advantages of technical simplicity, easiness in acquisition of starting materials, high yield and low production cost.
- -
-
Paragraph 0037; 0038; 0050; 0051
(2017/11/16)
-
- ANTI-HIV COMPOUNDS
-
This invention provides, among other things, tetrahydroisoquinolines useful for treating viral infections, pharmaceutical formulations containing such compounds, as well as methods of inhibiting the replication of a virus, such as HIV, or treating a disease, such as AIDS.
- -
-
Paragraph 0316-0317
(2016/07/05)
-
- Synthesis and crystal structure of (4s)-4-benzyl-3-(4,5-dimethoxy-2-methylbenzoyl)- 2,2-dimethyl-1,3-oxazolidine
-
The synthesis of (4S)-4-benzyl-3-(4,5-dimethoxy-2-methylbenzoyl)- 2,2-dimethyl-1,3-oxazolidine 6 was performed in 7 steps starting from veratraldehyde 7. A new oxidizing system TBHP-ebselen 12 was used for oxidation of 4,5-dimethoxy-2-methylbenzaldehyde 11 into carboxylic acid 13, being the crucial step of the synthesis. The latter was transformed first to chiral amide 14 using (S)-phenylalaninol and then cyclised to oxazolidine 6. The spatial structure and the absolute configuration of the latter one was confirmed by X-ray study.
- Chrzanowskak, Maria,Meissner, Zofia,Chrzanowska, Joanna M.,Gzella, Andrzej K.
-
p. 730 - 739
(2015/03/04)
-
- First total synthesis of the phenolic 7,8-dihydro-8-oxoprotoberberine alkaloid, cerasonine
-
First total synthesis of the phenolic protoberberine, cerasonine, was accomplished through a coupling reaction between o-toluamide and benzonitrile. This key step provided the 3-arylisoquinoline which was then successfully converted to 7,8-dihydro-8-oxoprotoberberine through an intramolecular S N2 reaction.
- Le, Thanh Nguyen,Cho, Won-Jea
-
experimental part
p. 1026 - 1029
(2009/07/18)
-
- Synthesis and biological activity of C-3' ortho dihydroxyphthalimido cephalosporins
-
A series of C-3' ortho dihydroxyphthalimido cephalosporins 3~7 has been prepared by reaction of C-3' aminomethyl cephalosporin 411) with the corresponding N carboethoxyphthalimides 23 ~ 25, 37, 38. These new caphalosporins exhibit excellent in vitro Gram-negative activities, including Pseudomonas aeruginosa, excellent β-lactamases stability and pharmacokinetics equivalent or better than ceftriaxone.
- Baudart,Hennequin
-
p. 1458 - 1470
(2007/10/02)
-
- Cephem compounds
-
Cephalosporin antibiotics having a 3-position substituent of the formula: STR1 are described, wherein X is --CO--, --SO2 -- or --COCH2 --; Y is --CO--, --SO2 -- or --CH2 --; Q is a benzene, pyridine or naphthalene ring, R1 and R2 are ortho with respect to each other and are independently hydroxy or of the formula O--M wherein M is a moiety and the O--M bond is cleavable in vivo and ring Q may be further substituted by a variety of atoms and groups. Processes for their preparation and use are described.
- -
-
-
- Syntheses of Antibacterial 2,4-Diamino-5-benzylpyrimidines. Ormetoprim and Trimethoprim
-
A general and mild method for the synthesis of 2,4-diamino-5-benzylpyrimidines was achieved by the Friedel-Crafts reaction between 2-(methoxymethylene)-3-methoxypropanenitrile (10) and an activated aromatic substrate followed by treatment with guanidine.The method is illustrated by a synthesis of ormetoprim (2) in 75percent overall yield from 3,4-dimethoxytoluene (12).Efficient syntheses of trimethoprim (1) and 2 were also accomplished via prior base-catalyzed 1,3-prototropic isomerization of cinnamonitriles 19 and 20, respectively, followed by condensation with guanidine. 12 was prepared from 3-bromo-4-methoxytoluene by a Cu(I)-catalyzed displacement of bromine by methoxide and 4,5-dimethoxy-2-methylbenzaldehyde was obtained from 12 in 87percent yield by a pyridine-catalyzed Vilsmeier reaction using DMF-POCl3.
- Manchand, Percy S.,Rosen, Perry,Belica, Peter S.,Oliva, Gloria V.,Perrotta, Agostino V.,Wong, Harry S.
-
p. 3531 - 3535
(2007/10/02)
-
- Synthesis based on Cyclohexadienes: Part 4. Novel Synthesis of the 6-Aryl-2,4-dimethoxybenzoates. Alternariol and Methyl Trimethylaltenusin
-
A novel method for the preparation of 6-aryl-2,4-dimethoxybenzoic acids involving the Alder-Rickert reaction of 1,5-dimethoxycyclohexa-1,4-dienes and arylpropiolic esters is described.This strategy has been extended to the synthesis of the mould metabolite alternariol and methyl trimethylaltenusin.
- Kanakam, Charles C.,Mani, N. S.,Rao, G. S. R. Subba
-
p. 2233 - 2237
(2007/10/02)
-
- SUBSTITUENT EFFECTS ON THE PHOTOCHEMISTRY OF o-TOLUALDEHYDES
-
The effect of 4-oxy and 4,5-dioxy substituents on the photochemical conversion of 2-methylbenzaldehydes to o-quinodimethanes (o-QDMs) has been studied.The presence of a 4-methoxy, or a 4 and 5-methoxy substituent prevented the photochemical formation of the o-QDM whereas 4-acetoxy and 4,5-diacetoxy-2-methylbenzaldehyde and the corresponding mesylates and tosylates were successfully converted to the o-QDMs.
- Charlton, James L.,Koh, Kevin
-
p. 5595 - 5598
(2007/10/02)
-
- 3-(substituted phenyl)phthalides
-
Process comprises the combination of the three steps of condensing 3-N(R)2 -4-X-benzoic acid with an aromatic or heterocyclic aldehyde, Y-CHO, under acidic conditions to produce 3-Y-5-X-6-N(R)2 phthalide (II), condensing said phthalide with a compound of the formula Z-H under alkaline or acid conditions to produce 2-(α-Y-α-Z)methyl-4-X-5-N(R)2 benzoic acid (III), and oxidizing said benzoic acid to produce 3-Y-3-Z-5-X-6-N(R)2 phthalide (I) where: R is hydrogen, non-tertiary alkyl of one to four carbon atoms, benzyl or substituted benzyl; X is hydrogen or halo; Y is 4-R1 -3-R2 -2-R1 -phenyl, 1-R5 -2-R6 -5/6-R4 -3-indolyl, 9-R7 -3-carbazolyl, 9-julolidinyl, 3,4-dioxymethylenephenyl, 2-thienyl, 1-R8 -2-pyrrolyl, or 4-pyridinyl; and Z is 4-R1 -3-R2 -2-R1 -phenyl, 1-R5 -2-R6 -5/6-R4 -3-indolyl or 1-R8 -2-pyrrolyl which are useful as colorless precursor color formers in carbonless duplicating and in thermal marking systems. The intermediates, 3-Y-5-X-6-N(R)2 phthalides (II) and 2-(α-Y-α-Z)methyl-4-X-5-N(R)2 benzoic acids (III) also have utility as colorless precursor color formers in carbonless duplicating and thermal marking systems.
- -
-
-
- SYNTHESIS OF -2'-METHYLRETICULINE AND ITS INCORPORATION INTO ALKALOID FRACTIONS OF PAPAVER SOMNIFERUM
-
-2'-Methylreticuline has been synthesized by standard methods.This modified opium alkaloid precursor is efficiently incorporated by aberrant biosynthesis into alkaloid fractions of Papaver somniferum, particularly into a highly purified codeine fraction.Key Word Index - Papaver somniferum; Papaveraceae; morphine alkaloids; aberrant biosynthesis; 2'-methylreticuline.
- Waddell, Thomas G.,Rapoport, Henry
-
p. 469 - 472
(2007/10/02)
-
- INTRODUCTION OF A HYDROXYL GROUP INTO THE CREOSOL MOLECULE
-
The introduction of a hydroxyl group into the molecule of 2-methoxy-4-methylphenol through Rieche formylation and Baeyer-Villiger oxidation was investigated.With dichloromethyl methyl ether meta-formylation of creosol occurs.
- Kozlova, I. V.,Obol'nikova, E. A.,Chupina, L. N.,Bekker, A. R.,Samokhvalov, G. I.
-
p. 296 - 299
(2007/10/02)
-
- Benzocyclobutenes. Part 5. Synthesis of 4-Hydroxy-, 4,5-Dihydroxy-, and 3,6-Dihydroxy-benzocyclobutene-1,2-dione (Benzologues of Semisquaric and Squaric Acid)
-
4-Methoxy- and 4,5-dimethoxy-benzocyclobutene-1,2-dione have been made by flash vacuum pyrolysis of the anthracene adducts of the corresponding phthalazine-1,4-diones which were prepared from the appropriate methoxyphthalic anhydrides. 3,6-Dimethoxybenzocyclobutene-1,2-dione has been prepared from 2-amino-3,6-dimethoxybenzoic acid via the addition of 3,6-dimethoxybenzyne to vinylidene chloride followed by hydrolysis of the resulting 1,1-dichloro-3,6-dimethoxybenzocyclobutene, bromination, and further hydrolysis.The three methoxy-diones and 4,5-dimethoxyphthalaldehyde have been demethylated by heating them with hydrobromic acid and the pKa values of the four hydroxy-compounds have been measured.Preliminary experiments on the synthesis of 4,5-dimethoxybenzocyclobutene are recorded.
- Abou-Teim, Omar,Jansen, Robert B.,McOmie, John F. W.,Perry, David H.
-
p. 1841 - 1846
(2007/10/02)
-