Benzoic 1,4-dihydro

Even in Ugi reactions of chiral 4,5-dihydro-3//-pyrrole derivatives with aryloxy substituents vicinal to the cWo-cyclic imino group, a low stereoselectivity was found with either chiral or achiral isocyanides and benzoic acid leading to substituted 2-aminoearbonyl-3-aryl-oxy-1 -benzoylpyrrolid ine derivatives82. 

Benzoic acid, 1,1-dimethylethyl ester [Benzoic acid, fe/7-butyl ester] as impurity in /erV-butyllithium, 55, 125 Benzoic acid, 4 methoxy, methyl ester [Anisic acid, methyl ester], 55, 40, 41 3//-2-BENZOPYRAN-3-ONE, 1,4-dihydro-... 

Under aerobic conditions, Beijerinckia sp. degraded biphenyl to c75-2,3-dihydro-2,3-dihydroxybiphenyl. In addition, Oscillatoria sp. and Pseudomonas putida degraded biphenyl to 4-hydroxybiphenyl and benzoic acid, respectively (Kobayashi and Rittman, 1982). 

Soil. In unsterilized soils, 58% of C-labeled sulfometuron-methyl degraded after 24 wk. Metabolites identified were 2,3-dihydro-3-oxobenzisosulfonazole (saccharin), methyl-2-(amino-sulfonyl) benzoate, 2-aminosulfonyl benzoic acid, 2-(((aminocarbonyl)amino)sulfonyl) benzoate, and [ C]carbon dioxide. The rate of degradation in aerobic soils was primarily dependent upon pH and soil type (Anderson and Dulka, 1985). The reported half-life in soil was approximately 4 wk (Hartley and Kidd, 1987). 

Sodium in liquid ammonia and ethanol reduced benzoic acid to 1,4-dihy-drobenzoic acid. Reduction of p-toluic acid was more complicated and afforded a mixture of cis- and rranj-l,2,3,4-tetrahydro-p-toluic acid and cis-and tra j-l,4-dihydrotoluic acid. m-Methoxybenzoic acid yielded 1,2,3,4-tetrahydro-5-methoxybenzoic acid, and 3,4,5-trimethoxybenzoic acid gave l,4-dihydro-3,5-dimethoxybenzoic acid in 87% yield (after hydrogenolysis of the methoxy group para to carboxyl) [984. In the case of 4 -methoxy-biphenyl-4-carboxylic acid, sodium in isoamyl alcohol at 130° reduced completely only the ring with the carboxylic group, thus giving 92% yield of 4-(p-methoxyphenyl)cyclohexanecarboxylic acid [955]. 

The cyclocondensation of l,3-amino alcohols with carboxylic acid derivatives is a method often applied for the synthesis of 5,6-dihydro-4/7-l,3-oxazines <1996CHEC-II(6)301 >. Ebsorb-4, a weakly acidic zeolite-type adsorbent with 4 A pore size, proved an efficient catalyst of the cyclization of benzoic acid and 3-aminopropanol <2002TL3985>. In the presence of zinc chloride as a catalyst, the expulsion of ammonia drove the reactions of 3-aminopropanol with nitriles to completion, affording 2-substituted 5,6-dihydro-47f-l,3-oxazines in good yields... 

Bromination of l,2-dihydro-l-methylbenzo[d][l,2,3]diazaborine (188 X = Y = H) gave substitution in the 4-position to give (188 X = Br, Y = H). Oxidation of the brominated product with potassium permanganate led to the isolation of 2-bromobenzoic acid, which was erroneously taken as evidence for bromination in the 5-position. However, a more careful oxidation gave benzoic acid, suggesting that the original procedure oxidized the bromine atom to elemental bromine, which then carried out a deboronating bromination. 

Phenyl benzoate Benzoic acid, phenyl ester (8,9) (93-99-2) Dihydrocoumarin 2H-1-Benzopyran-2-one, 3,4-dihydro- (9) (119-84-6)... 

The Birch reduction of 3,4,5-trimethoxybenzoic add 17a b (cognate preparation in Expt 7.19) is of interest in that the product is 1,4-dihydro-3,5-dimethoxy-benzoic add (46) thus revealing that in this reduction the 4-methoxy group is removed by hydrogenolysis. The product possesses two methyl vinyl ether residues which are labile under aqueous acidic conditions to yield the saturated diketone, 3,5-diketocyclohexanecarboxylic add (47). 

This product was reacted with 2-carboxybenzaldehvde whereupon 2-/2-(thienyl)-vinyl/-benzoic acid (IV was obtained IV was hydrogenated to 2-/2-(thienyl)-ethyl/-benzoic acid (V). Cyclisation. under the influence of polyphosphoric acid, (PPA , resulted in 9,lo-dihydro-4H-benzo[4,5 J-cyclohepta [1,2-b]-thio-phene-4-one (VI). 

Chemical Name Benzoic acid, 5-(4,5-dihydro-2-phenyl-3H-benz[e]indol-3-yl)-2-hydroxy-... 

A mixture of 20.0 g (0.076 mole) of 2-phenacyl-l-tetralone, 11.6 g (0.076 mole) of 5-aminosalicyclic acid, and 70 ml of glacial acetic acid was heated under reflux for 4 hours, cooled, diluted with 10 ml of water and filtered. The filter cake was washed with water and dried to provide 15.5 g of solid, 5-(4,5-dihydro-2-phenyl-3H-benz[e]indol-3-yl)-2-hydroxy-benzoic acid. MP 215°-218°C. Recristallization from benzene-cyclohexane gave 6.5 g (22%) of yellow crystals, MP 245°-247°C. 

C) Preparation of 9,10-Dihydro-4H-Benzo[4,5]Cyclohepta[l,2-b]Thiophen-(4)-One 200 ml of 85% phosphoric acid and 112 g of phosphorus pentoxide are heated to 135°C. 7.0 g of o-[2-thienyl-(2 )-ethyl]benzoic acid are then introduced while stirring thoroughly over a period of 30 min. Stirring is then continued for another hour at 135°C and the reaction mixture is then stirred into 1 liter of ice water. Extraction is then effected 3 times, using 250 ml ether portions, the ethereal extract is washed with 2 N sodium carbonate solution, dried over sodium sulfate and reduced in volume by evaporation. The residue is boiled up with 55 ml of ethanol, the solution freed of resin by decanting and then stirred at room temperature for 6 hours with animal charcoal. It is then filtered off, reduced in volume in a vacuum and the residue distilled. BP 120° to 124°C/0.005 mm, nD24-5 = 1.6559. 

The yields obtained on dominating the following amines further illustrate the wide utilitybf hypophosphorous acid 2,4-diethyl-6-bromoaniliae (70%),89 3-nitro-4-aminophenylarsonic acid (45%),90 3-amino-6-bromo-benzoic acid (75%),13 3,3 -dimethylbenzidine (76-82%),80-81 4-amino-7-chlorohydrindone-1 (85%),91 5-methyl-8-aminoquinoline (72%) 84 o-(/3-phenylethyl)-aniline (XXII) (47%).86 In the last case, when ethanol is used dibenzyl is not obtained instead the products are 9,10-dihydro-phenanthrene (co. 50%) and o-(j8-phenylethyl)-phenol (23%).66... 

Amino-6-nitro-Fischer s base (36, R = N02) was reduced to the 5,6-diamino compound (36, R = NH2) in 80% yield, which (as its hexachlorostannate salt) was condensed with benzoic acid and with benzil to give, respectively, a 68% yield of 5,7,7-trimethyl-6-methylene-6,7-dihydro-5 7/-pyrrolo[2,3-/]-benzimidazole (37) and a 62% yield of 6,8,8-trimethyl-7-methylene-2,3-diphenyl-7,8-dihydro-6 7/-pyrrolo[2,3-g]quinoxaline (38).42 Spiropyrans from these linearly annellated Fischer s bases were not reported they likely would color upon irradiation with blue light. 

X-ray studies were also performed for bis(l,2,3,5-tetramethyl-4-nitropyrazolium salt [105], l-methyl-4(5)-nitro-5(4)-styrylimidazole [82], I -(/V-morpholino )-4-nitroimidazole [83], 1-sodium salt of 4-[2-[(l-methyl-5-nitro-2-imidazolyl)thio] ethoxy]-benzoic acid [106], l-methyl-4-nitro-5-chloroimidazole [107], omidazole [81], megazole [108], l-methyl-2-nitro-5-vinylimidazole [42], l-[2-(ethylsulfonyl) ethyl]-2-methyl-5-nitroimidazole (tinidazole) and one of the basic tinidazole metabolites - ammonium salt of l-[2-(ethylsulfonyl)ethyl]-4, 5-dihydro-2-methyl-4-nitroimidazole-5on [109], morpholino nitroimidazole derivatives [110, 111], l-(2-bromoethyl)-2-methyl-5-nitroimidazole [112], l-(4-chlorophenacyl)-2-methyl-... 

Phenyl 2-hydroxy-4-(3,3,3-trifluoromethyl-2-hydroxy-2-methylpropionylamino)benzoic acid is the latest chemical agent designed to treat alopecia supplanting 6-amino-1,2 dihydro-l-hydroxy-2-aminopyrimidine (Minoxidil) (I) (1) and pyrimidine oxide derivatives (II) (2), (III) (3), and (IV) (4). 

The history of saccharin (1)B since its discovery by Remsen and Fahlberg in 1879,6> 7 is reflected in a host of names e.g., 2,3-dihydro-3-oxo-benzisosulfonazole 1,2-benzoisothiazolin-3-one-1,1 -dioxide o-sul-fobenzimide o-benzosulfimide benzoic sulfimide benzoic sulfon-imide benzoic sulfinide l-benzosulfonazol-2(l)-one besides clearly... 

SYNS ANHYDRO-o-SULFAMINEBENZOIC ACID 3-BENZISOTHIAZOLINONE-l,l-DIOXIDE o-BENZOIC SULPHIMIDE o-BENZOSULFIMIDE BENZO-SULPHIMIDE BENZO-2-SULPHIMIDE o-BENZOYL SULFIMIDE o-BENZOYL SULPHIMIDE 1,2-DIHYDRO-2-KETOBENZISOSULFONAZOLE 1,2-DIHYDRO-2-KETOBENZISOSULPHONAZOLE 2,3-DIHYDRO-3-OXOBENZISOSULFONAZOLE 2,3-DIHYDRO-3-OXOBENZISOSULPHONAZOLE GARANTOSE GLUCID GLUSIDE HERMESETAS... 

SYNS BENZOIC acid, 3-((3-(ETH0XYMETHYL)-S-FLUORO-3,6-DIHYDRO-2,6-DIOXO-l(2H)-PYRIMIDINYL)CARB ONYL)-, BOF-A2 EMITEFUR... 

SYNS BENOVOCYLIN BENZHORMOVARINE BENZOATE d OESTRADIOL (FRENCH) BENZO-ESTROFOL BENZOFOLINE BENZO-GYNOESTRYL BENZOIC ACID ESTRADIOL DIFFOLLISTEROL DIFOLLICULINE DIHYDROESTRIN BENZOATE DIHYDRO-FOLLICULIN BENZOATE DIMENFORMON BENZOATE DIMENFORMONE DIOGYN B EBZ ESTON-B ESTRADIOL BENZOATE P-ESTRADIOL BENZOATE ESTRADIOL-17-p-BENZOATE ESTRADIOL-17-P-3-BENZOATE P-ESTRADIOL-3-BENZOATE 17-P-ESTRADIOL BENZOATE 17-p-ESTRADIOL-3-BENZOATE ESTRADIOL MONOBENZOATE 17-P-ESTRADIOL MONOBENZOATE ESTRA-1,3,5(10)-TRIENE-3,17-DIOL (17-P)-3-BENZOATE ESTRA-1,3,5(10)-TRIENE-... 

BENZOIC ACID, 2,2 -DISELENOBIS- see SBU150 BENZOIC ACID ESTRADIOL see EDPOOO BENZOIC ACID, 3-((3-(ETHOXYMETHYL)-5-FLUORO-3,6-DIHYDRO-2,6-DIOXO-l(2H)-PYRDVnDINYL)CARB ONYL)-, see BDN600 BENZOIC ACID, 3-FORMYL-2,4-DIHYDROXY-6-METHYL-, 3-HYDROXY-4-(METHOXYCARBONYL)-... 

The first sets of experiments carried out on the reduction of benzoic acids gave mixtures of dihydro and tetrahydro derivatives. This is hardly surprising in the light of the Van Bekkum study. The first systematic investigation appears to have been carried out on p-lsopropylbenzoic acid (84 Scheme 15), ° for which it was found that reduction by lithium-ammonia at -70 C followed by the addition of ethanol and then ammonium chloride at 5 min intervals furnished a 2 1 mixture of trans- and c/i-1,4-dihydro derivatives (85). In the absence of ammonium chloride the 3,4-dihydro isomer (86) was obtained and this could be reduced further to a 2.5 1 mixture of the tetrahydro derivatives (87) (ammonium chloride quench) and ( )-phellandric acid (88). 

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