Cyclic imides, preparation

Otherwise, the sera bind groups of compounds with related structures. In an attempt to improve selectivity for the biologically important 3P-hydroxy-GAs, monoclonal antibodies were raised to a 19-20-cyclic-imide prepared from GA,7 (Fig. 4) [81]. In this immunogen the p-face of the GA is exposed. However, curiously, this hapten had a... 

Cyclic imides can be prepared by heating the ammonium salts of dicaiboxyhc... 

The procedure described here for the preparation of succinimide silver salt is a modification of one reported for the formation of the silver derivative of maleimide. The alkylation step is modeled after the procedure of Comstock and Wheeler/ who prepared 2-ethoxypyrrolin-5-one in unspecified 3deld, and is an improvement over a later procedure developed in the laboratories of the submitters/ The general scheme has been successfully applied to the preparation of a variety of 2-ethoxypyrrolin-5-ones (Table 1) as well as 6-ethoxy- and 6-propoxy-4,5-dihydro-2(3H)-pyridone from the corresponding five- and six-membered cyclic imides/... 

Maleic anhydride derivatives are readily making it possible to perform their transformations into photochromic N-alkyl-substituted dithienylma-leimides with primary amines. This method was used to prepare cyclic imides 187 in anhydrous methanol or ethanol at 20-80°C in 67-90% yields (02ZOR1390) and N-alkyl(aryl) derivatives 188 based on thieno[3,2-b]pyr-role (03IZV1719) in 70-90% yields. 

Following resolution with (—)-quinine, (+)-465 was transformed into the (-l->2-formamido derivative which was condensed with the acid chloride of (+)-465 to give the secondary amide 468. From this point, the cyclic imidate salt 469 was prepared, but cyclization to the dodecahedrane nucleus could not be realired With Thiele s add as starting material, several routes to triquinacene and 2,3-dihydrotriquinacen-2-one 462) have been developed Triquinacene reacts with Mo(CO)g to give tricarbonyl(triquinacene)molybdenum (470) and with (CHjCI -... 

Some enantiomerically pure substituted 2-oxazolidinones are excellent as chiral auxiliaries. From the pioneering studies 2 conducted in the early 1980 s of the uses of such auxiliaries has emerged what is perhaps the most widely used method today for the preparation of enantiomerically highly enriched a-alkylalkanoic acids, alcohols and aldehydes, that is, the alkylation of enolates from chiral 3-acylated 2-oxazolidinones followed by auxiliary removal2 59. The early work has been reviewed60-62. These enantiomerically pure cyclic imide auxiliaries have been used not only for alkylations but also in a plethora of a-functionalization reactions, such as diastereoselective aldol, a-hydroxylation, a-amination and Diels-Alder reactions and these are discussed elsewhere in this volume. 

Tritylamine linkers have not been extensively used for the attachment of amides, probably because A -tritylamides are difficult to prepare. This is not the case for strongly acidic amides and cyclic imides, which are readily N-tritylated with trityl chlo-... 

Important method for preparation of cyclic imides from cyclic anhydrides. 

The preparation of 1,7-naphthyridines by ring expansion of cyclic imides has previously been discussed (see Section III, A). 

A number of cyclic imides, such as uracil (11), can be used in conjunction with a nitrogenous base.64 These compounds are added to hydroxylamine developer formulations. Several thioether-substituted 2,4- or 4,6-dihydroxypyrimidines, such as (12), are useful.65 Thioether-con-taining carboxylic acids can be used in the preparation of electrically conducting transferred silver images. These include 3-thiapentanoic acid, 3-thiapentanedioic acid and 3,6-dithiaoctanedioic acid.66 Mercaptobenzoic acids are used alone or with a cyclic imide solvent to produce lithographic... 

For the preparation of anthranilic acid the starting material is phthalimide, the cyclic imide ring of which is opened by alkaline hydrolysis in the first step of the reaction to give the sodium salt of phthalimidic acid (the half amide of phthalic acid). The intermediate undergoes the Hofmann reaction in the manner outlined on p. 783 yielding o-aminobenzoic acid (anthranilic acid). 

A radical fragmentation sequence has been used for the preparation of 8-membered cyclic imides [95H49]. Treatment of the carbinolamide 241 with diacetoxyiodobenzene gave the imide 244 in low yield. The major product in this reaction is a 5-membered cyclic imide, a product arising from an alternative C-C bond cleavage. 

Several blue tetra- and octanuclear Pt complexes, prepared upon reaction of cis-[Pt(NH3)2(H20)2]2+ with open and cyclic amides, as well as cyclic imides and a uracil nu-cleobase, and comprised of binuclear building blocks interacting through Pt-Pt bond formation, have been isolated and structurally characterized in recent years. Without exception, the average Pt oxidation state in these compounds is 2.25. Nevertheless, the structure and mode of action as antitumor agents of the Platinum Pyrimidine Blues , as prepared by Rosenberg in the early 70 s, remain elusive. This account represents a summary of our present knowledge on cationic Platinum Blues , with a focus on those blues obtained from cis-[Pt(NH3)2(H20)2]2+ and pyrimidine nucleobases, and presents speculations on reasonable alternative structures. 

Imido chlorides such as the oxathiazolines (179) behave typically, reacting with water to form cyclic imides, and with amines and sulfur nucleophiles to yield the expected derivatives (75MI43401). The chlorodithiazolone (77) is itself prepared by hydrolysis of the chlorodifluoro compound (180) (71CB2732). 

Benzoxazoles have been prepared by intramolecular reaction of a phenolic —OH groiq) with a Beckmann intermediate (equation 30). A cyclic imidate was isolated in high yield from tosylation and in situ Beckmann reaction of the erythromycin-derived oxime (4[Pg.698]

The preparation of imides was reviewed recently and many methods are recommended. - Under somewhat drastic conditions ( > 200 °C) dicarboxylic acids react with ammonia, or compounds which are able to produce ammonia like urea, thiourea, formamide, sulfamic acid, ammonium carbonate and others to form cyclic imides (equation 52). Monoammonium salts of dicarboxylic acids give imides under pyrolytic conditions when distilled under reduced pressure. ... 

PROTECTING GROUPS - Cyclic imide disulfides from primary amines can be prepared by the scheme below. Treatment with mercaptoethanol under very mild conditions gives back the starting amine. 

Phosphorus-containing enamines have been prepared by phosphorylation of N-vinyl substituted tertiary amides, lactams and cyclic imides with phosphorus pentachloride ". Addition of amines to diphosphoryl alkynes has been described. Addition of RR NH [R = H, Ri = Me, cyclohexyl, PhCH2 RR = (CHj) to (Et0)2P(0)C=CP(0K0Et2)2 in CH2CI2 at 25 °C gave 93-100% of (Et0)2P(0)C(NRRi)=CHP(0)(0Et2)2 . Speziale and coworkers have studied the reactions of phosphorus compounds with trichloroacetamides. 

Preparation of novel specific aminopeptidase inhibitors with a cyclic imide skeleton 00YZ909. 

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