Acetic succinimid

A more active product is obtained by the following slight modification of the above procedure. Dissolve the succinimide in a slight molar excess of sodium hydroxide solution and add the bromine dissolved in an equal volume of carbon tetrachloride rapidly and with vigorous stirring. A finely crystalline white product is obtained. Filter with suction and dry thoroughly the crude product can be used directly. It may be recrystallised from acetic acid. 

Further versatihty was added to the range of substituents available for introduction into the 6a-position by use of the 6a(succinimido-oxy) derivative (18) prepared by treatment of the 6a-(methylthio) derivative (17) with A/-hydroxy-succinimide and silver(I) acetate in dimethylformamide in virtually quantitative yield. In this way the 6a-cyanopeniciILin (19, X = CN), 6a-viny1penici11in (19, X = CH=CH2) and 6a-pheny1penici11in (19, X = C H ) could be prepared in high yield (43). 

Condensation of allyl isocyanate with succinimide affords the cyclic diacylurea 39. Acid hydrolysis leads to ring opening of the succinimide (40). Oxymercuration of the terminal olefin bond with mercuric acetate in methanol solution affords the diuretic meralluride (41). ... 

The cyclized analog of meralluride is prepared by a similar synthesis. Thus, condensation of camphoric acid (42) (obtained by oxidation of camphor) with ammonia gives the bicyclic succinimide (44). Reaction with allyl isocyanate followed by ring opening and then reaction with mercuric acetate affords the mercury derivative (45) as the acetate rather than the hydroxide as above. Reaction with sodium chloride converts that acetate to the halide (46). Displacement on mercury with the disodium salt of thioglycollic acid affords the diuretic mercaptomerine (47). ... 

The reaction scheme is rather complex also in the case of the oxidation of o-xylene (41a, 87a), of the oxidative dehydrogenation of n-butenes over bismuth-molybdenum catalyst (87b), or of ethylbenzene on aluminum oxide catalysts (87c), in the hydrogenolysis of glucose (87d) over Ni-kieselguhr or of n-butane on a nickel on silica catalyst (87e), and in the hydrogenation of succinimide in isopropyl alcohol on Ni-Al2Oa catalyst (87f) or of acetophenone on Rh-Al203 catalyst (87g). Decomposition of n-and sec-butyl acetates on synthetic zeolites accompanied by the isomerization of the formed butenes has also been the subject of a kinetic study (87h). 

Succinimide (9.9 g, 100 mmol), ethyl cyanoacetate (21.28 mb, 200 mmol), HMDS 2 (42.2 mb, 200 mmol), and (NH4)2S04 (0.7 g, 5 mmol) are heated for 34 h under reflux with magnetic stirring. After cooling the colored residue is chromatographed on a silica gel column (25 cm X 6 cm i.d.) with hexane-ethyl acetate (1 1) as mobile phase. The first fractions contain ca 3% pure bis-product 382,... 

PGIP, purified fi om P.vulgaris hypocotyls [11], was immobilized to the sensor ch via amine coupling. A continuous flow of HBS buffer (5 pl/min) was mantained over the sensor surface. The carboxylated dextran matrix of the sensor surface was first activated by a 6-min injection of a mixture of N-hydroxy-succinimide and N-ethyl-N - (3-diethylaminopropyl) carbodiimide, followed by a 7-min injection of PGIP (lOng/pl in 10 mM acetate, pH 5.0). Hie immobilization procedure was con leted by a 7-min injection of 1 M ethanolamine hydrochloride to block the remaining ester groups. 

Dissolve 71 g. of P-methylnaphthalene in 460 g. (283 ml.) of A.B. carbon tetrachloride and place the solution in a 1 -litre three-necked flask equipped with a mechanical stirrer and reflux condenser. Introduce 89 g. of JV-bromosuccinimide through the third neck, close the latter with a stopper, and reflux the mixture with stirring for 16 hours. Filter ofiT the succinimide and remove the solvent under reduced pressure on a water bath. Dissolve the residual brown oil (largely 2-bromomethyl naphthalene) in 300 ml. of A.R. chloroform, and add it to a rapidly stirred solution of 84 g. of hexamine in 150 ml. of A.R. chloroform contained in a 2-litre three-necked flask, fitted with a reflux condenser, mechanical stirrer and dropping funnel maintain the rate of addition so that the mixture refluxes vigorously. A white solid separates almost immediately. Heat the mixture to reflux for 30 minutes, cool and filter. Wash the crystalline hexaminium bromide with two 100 ml. portions of light petroleum, b.p. 40-60°, and dry the yield of solid, m.p. 175-176°, is 147 g. Reflux the hexaminium salt for 2 hours with 760 ml. of 60 per cent, acetic acid, add 160 ml. of concentrated hydrochloric acid, continue the refluxing for 5 minutes more, and cool. Extract the aldehyde from the solution with ether, evaporate the ether, and recrystallise the residue from hot -hexane. The yield of p-naphthaldehyde, m.p. 69-60°, is 60 g. 

The earliest oxidations were effected with nitrous fumes and later with mercuric oxide and isoamyl nitrite.74 Lead tetraacetate in acetic acid is in many cases the reagent of choice, but the removal of by-products can present some difficulties.75 IV-Haloimides and amides in alcoholic solutions have been reported to yield essentially pure tetrazolium salts76 and have been found specially useful in the preparation of heteroaryl-substituted tetrazolium salt.77,78 The novel formazans 49 have been successfully oxidized to 50 using 7V-chloro succinimide (Eq. II).79 tert-Butyl hypo-... 

A-(benzyloxycarbonyloxy)succinimide (CBz-OSu, 12.3 g) sodium hydrogen carbonate distilled water ethyl acetate... 

Bugge brominated thienothiophenes 1 and 2 with IV-bromo-succinimide in glacial acetic acid to 2-bromothieno[2,3-6]thiophene (66%) and 2-bromothieno[3,2-6]thiophene (55%). The structure of 2-bromothieno[2,3-6]thiophene was confirmed by the replacement of bromine by lithium at —70° followed by carbonation to thieno[2,3-6j-thiophene-2-carboxylic acid 2-bromothieno[3,2-fe]thiophene was independently prepared by the treatment of 2-lithiothieno[3,2-6]thiophene with one equivient of bromine at —70°. The 2-bromo derivatives of thienothiophenes 1 and 2 decompose within several hours at 20°, but remain uncWged for weeks at —15°. 

Miscellaneous Compounds. A saturated spirocychc pyrrohdine serves as the nucleus for a diamine that has been described as a hypohpemic agent. Treatment of the carbanion of the substituted cylcohexane carboxyhc ester (20-1) with methyl bromoacetate leads to the alkylation and formation of the diester (20-2). Saponification of the ester groups followed by reaction with acetic anhydride leads to ring closure of the succinic anhydride (20-3). Condensation with ammonia leads to the succinimide (20-4). The side chain is then added by alkylation of the anion on nitrogen with l-bromo-4-dimethylaminobutane (20-5). Reaction of this last intermediate with lithium aluminum hydride leads to the reduction of the carbonyl groups to methylene. This affords the pyrrolidine (20-6) atiprimod [22]. 

Hoffman et al. [46, 47] found that an LCST polymer remains strongly bound to a substrate, especially to cellulose acetate (CA), at a temperature above its LCST, whereas most of the adsorbed polymer molecules are easily rinsed off below the LCST. For instance, they synthesized a room-temperature-precipit-able terpolymer (LCST = 7-13 °C), consisting of IPAAm, A-butylacrylamide (BAAm) and N-acryloxy succinimide (NASI), which was conjugated to a murine monoclonal antibody. They developed the membrane-affinity concentration immunoassay [48]. 

When 2,2-disubstituted 1,3-dioxolanes were employed, mono- or poly-chlorination of the side chain was observed on the carbon atom a to the acetal grouping. Incidentally, it should be noted thatN-bromo-succinimide, N-chlorosuccinimide, and trichlorotetrahydrotriazine-trione were found to be effective for the preparation of bromoacetates from O-ethylidene derivatives this might be useful when O-benzyli-dene derivatives are not readily available, or when a problem arises due to the fact thatO-benzoyl groups are, in general, more difficult to remove than O-acetyl groups. 

A mixture of methyl (2-methylphenyl)acetate (46 82.0 g, 0.5 mmol), NBS (89.0 g, 0.5 mmol), benzoyl peroxide (1.0 g), and CC14 (800 mL) was heated under reflux for 2h while irradiating with a 750 W light source. The precipitated succinimide was then filtered off, the solvent removed, and the residue distilled under reduced pressure to give 43 yield 90.1 g (74%). 

Succinimide and DMAD give a Michael 1 1 adduct,113 but iV-bromo-succinimide with acetylenic esters in acetic acid led to electrophilic addition of bromine to the triple bond.114... 

Figure 5 Covalent coupling of cyclic peptide moieties to human serum albumin (HSA). The depicted cyclic peptide, C SRNLIDC, in which C denotes the cyclizing cysteine residues, mimics the receptor binding site of PDGF-BB. First, a sulfhydryl group is introduced to the cyclic peptide by a reaction with succinimide-acetyl thioacetate (SATA). The primary amino groups of lysine in HSA are derivitized with maleimide-hexoyl-At-hydroxysuccinimide ester (MHS). Subsequently, the cyclic peptide is coupled to HSA. In this latter reaction, hydroxyl amine is used to remove the protecting acetate group from the sulfhydryl group of the cyclic peptide.

To a flask were added ethyl p-toluate (6 mmol), NBS (7.2 mmol), and AIBN (0.6 mmol) under an argon atmosphere. The mixture was well mixed and stirred for 2 min. Then, the mixture was heated at 60 °C for 1 h. After the reaction, ether was added to the mixture, and the formed succinimide was removed by filtration. The filtrate was evaporated and the residue was chromatographed on silica gel (eluent hexane/ethyl acetate = 1/1) to provide ethyl p-(a-bromo)toluate in 73% yield [45]. 

The synthesis of the derivatives (339)-(346) was carried out as shown in Scheme 28. Metalation of the acetal (336), followed by thiolation and alkylation, gave the ester derivative (337). Acetal deprotection to form (338) and subsequent treatment under Knoevenagel conditions with piper-idinium acetate in benzene afforded the desired ester (339). Reduction of compound (339) gave alcohol (340), which was converted to aldehyde (341) and protected as its acetal (342) under standard conditions. Deprotonation was effected by Bu"Li in THF at — 78 °C and subsequent conversion to the sulfonyl chloride was carried out by sequential treatment with sulfur dioxide and A-chloro-succinimide. Treatment of the sulfonyl chloride (343) with concentrated NH4OH in acetone provided the sulfonamide (344), which was deprotected (345) and subjected to reductive amination to provide compounds in the aminomethyl sulfonamide series (346). 

Aliphatic and alicyclic carbamates are nitrated smoothly and in excellent yields by a nitric acid-acetic anhydride mixture (4). Similarity, we have found that treating an acyl aliphatic amine and a urethane with one equivalent of nitronium tetrafluoroborate in acetonitrile at —30° C. gave the corresponding N-nitro derivatives in good to excellent yields. However, diacylamines are more difficult to nitrate, and Kauffman and Burger (9) have reported that nitrating succinimide required 13 hours... 

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