Tosylamino acid

N-Protective group. Tosyl chloride reacts with amino acids in alkaline solution to give N-tosylamino acids. The protective group is removed by reductive cleavage with sodium in liquid ammonia. The tosyl group is particularly useful for protection of the w-amino groups of lysine and ornithin peptides. 

The synthesis of 3-aryltetrahydroisoquinolines was accomplished by electrophilic aromatic substitution of polysubstituted phenols and phenyl ethers with Lewis acid-generated tosyliminium ions of 2-tosyl-3-methoxytetrahydroisoquinoline derivatives <00SL801>. In addition isoquinoline was reported to react with N-tosylated (R)- or (S)-amino acid fluorides to afford optically active dihydroimidazoisoquinolinones. The reaction proceeds via acylation followed by attack of the tosylamino group at Cl of the intermediate 2-tosylaminoacylisoquinolinium salt <00TL5479>. 

Similarly, treatment of a-tosylamino-substituted allene 83 provided the expected a-amino ester 232 in good yield [74], The analogous reaction could also be performed with methoxyallene-aziridine adduct 46, which furnished enantiomerically pure /3-amino acid 233 [46], Although the ozonolysis approach seems to constitute a versatile and flexible method for the construction of a-amino and a-hydroxy esters, only a few examples have been reported so far. 

High yields of secondary amines are obtained when solutions of nitriles in acetic acid are hydrogenated at room temperature and pressure over a 5% rhodium-on-alumina catalyst (equation 4) hydroxy, ethoxycarbonyl and tosylamino substituents are not affected23. 

Following Scheme 4, L-a-aminosuberic acid can be obtained from iV-tosyI -L-gl utamic acid (5, n=2), upon protection of the a-carboxy and tosylamino groups as an oxazolidone 6, by extension of the side chain with the Amdt-Eistert method via the diazo ketone 7 by one methylene moiety in each cycle to produce in subsequent steps the L-a-aminoadipic acid [(5)-2-aminohexanedioic acid, 8, n = 2], L-a-aminopimelic acid [(5)-2-aminoheptanedioic acid, 8, n = 3] and finally L-a-aminosuberic acid [(5)-2-aminooctanedioic acid, 8, n = 4]J22 Treatment with HBr in AcOH was the method of choice for the acidolytic hydrolysis of the tosyl group. 23 ... 

Replacement of the benzene ring with an -butyl segment has been disclosed Scheme 3.124) [73, 248], Thus, methylation of 5-(A,-tosylamino)valeric acid [250], followed by coupling with diethyl L-glutamate, detosylation, alkylation with (26) HBr and hydrolysis afforded (594). 

A number of photochromic phenoxynaphthacenequinones were obtained using the initially synthesized 6-substituted ll-phenoxynaphthacene-5,12-quinones (IIIA) (Scheme 4).46 6,11-Dichloro-naphthacenequinone was the initial compound for the synthesis of these 6-chloro-ll-phenoxynaphthacenequinone compounds. 6-Chloro-1 l-tosylaminonaphthacene-5,12-quinone was obtained by interaction with phenox-ide potassium in DMSO and /j-tolucncsulfamidc in nitrobenzene, respectively. The latter compound was hydrolyzed in sulfuric acid to form 6-chloro-l 1-aminonaphtha-cene-5,12-quinone. The treatment of 6-chloro-l l-phenoxynaphthacene-5,12-quinone and 6-chloro-l l-aminonaphtacene-5,12-quinone with potassium phenoxide gave rise to 6-tosylamino- and 6-amino-ll-phenoxynaphthacene-5,12-quinones... 

Triethylamine (8) Ethanamine, N,N-diethyl- (9) (121-44-8) p-Toluensulfonyl chloride (8) Benzenesulfonyl chloride, 4-methyl- (9) (98-59-9) (lS,2S)-2-(N-Tosylamino)cyclohexanecarboxylic acid Cyclohexanecarboxylic acid, 2-[[(4-methylphenyl)sulfonyl]amino]-, (1S-trans)- (12) (110456-11-6)... 

The next five procedures of the final set illustrate the important process of preparation of enantiomerically pure materials beginning with readily available enantiomerically pure natural substances. Use of commercially available enantiomerically pure pyrrolobenzodiazepine-5,11-diones to prepare (1S,2S)-(+)-2-(N-TOSYLAMINO)CYCLOHEXANECARBOXYLIC ACID is described in the first procedure. The next preparation illustrates an optimized preparation of DIETHYL (2S,3R)-2-(N-tert-BUTOXYCARBONYL)AMINO-3-HYDROXYSUCCINATE... 

Tosic acid, see p-Toluenesulfonic add Af-Tosylamino adds, 1184 Tosylates, 958-959,1054 Tosyl azide, see p-Toluenesulfonyl azide Tosyl chloride, see p-Toluenesulfonyl chloride... 

Triarylbismuthine A -tosylimides react with benzaldehyde, benzoyl chloride and phenyl isocyanate to give A -tosylimine, A-tosylamide and A -tosylurea derivatives, respectively [91CL105] (Section 5.5.2.3). The imides oxidize secondary and benzylic alcohols to carbonyl compounds, sometimes accompanied by the concurrent formation of a diaryl(A -tosylamino)bismuthine [96JCR(S)24] (Section 5.2.4). When treated with acetic acid, the imides are converted to the corresponding triarylbismuth diacetates and sulfonamides (Scheme 3.9). 

Comparable acid- (or Lewis acid) -catalysed ring closures of 2-arylthio- and 2-aryloxy- -ketones, and -2-arylthio- and 2-aryloxyacetyl- chlorides lead to 3-substituted heterocycles and 3-oxygenated heterocycles, respectively. It is possible to combine the preparation of the arylthio-ketone and the ring closure steps utilising two solid-supported reagents in a one-pot procedure, as illustrated. Formation of 3-aryl-benzothiophenes by this route can be complicated by partial or complete isomerisation to the 2-aryl-heterocycle,however using boron trifluoride as the Lewis acid produces only the 3-aryl-isomer. 3-Tosylamino-benzofurans can be prepared from aryl glyoxal hydrates. ... 

Polyamine chain extension, 48-56 by acrylamide 51, 52. 53 by aziridine 48,49 by l-bromo-3-chloropropane, 55 by (2-bromoethyl)phthalimide, 51 by 3-bromopropylphthalimide, 53 by chloroacetonitrilc, 51 by chloroacetyl chloride. 50 by lV-(2-chloroethyl)acetamide, 52 by derivatives of chloroacetic acid. 50 by dichloro(o)-bromoalkyl)boranes. 56 by IV-ethylchloroacetamide, 52 by 3-phthalimidopropyl tosylate, 54 by /V-tosyl-2-bromoethylamine, 49 by 2-(N-tosylamino)ethyl tosylate. 49 by Af-tosylaminoacetyl chloride, 50 Polyamino diols. 59 Polyaza-crown macrocycles. 349-367 alkyl-substituted. 364.365 from bis-sulfonamides, 358-361 from diacid dichlorides, 352-357 from diesters, 352-357 from dihalides, 362-366 from diols, 366 from ditosylates. 362-366 Polyaza-crown macrocycles (miscellaneous), table. 392... 

Another synthesis of isoquinolines in which two ring bonds are formed involves the reaction of benzyl halides (74) with the sodium salt of N-(tosylamino)acetaldehyde dimethyl acetal. Treatment of the intermediate (75) with hydrochloric acid results both in ring-closure and aromatization (Scheme 48). ... 

When tosylamino or phthaloylamino carboxylic acids are warmed for a short time at 80-85° with an excess of CHCl2OCH3, the corresponding acid chlorides are formed in good yield. However, the acid chlorides formed as primary product from <%-(benzyloxycarbonylamino) acids and SOCl2 or an excess of CHCl2OCH3 split off benzyl chloride smoothly, giving A-(carboxy-amino) acid anhydrides1122 which are important intermediates in peptide synthesis. 

P-Amino acid derivatives of the f/fj-series have been obtained from the P-tosylamino-7-butyrolactone derived from L-aspartic acid (two steps). ... 

The synthesis of 6-chloro-l,2,3,7-tetrahydro-iV-tosylazepin-4-one from 3-[A-(2-chloroprop-2-enyl)-A-tosylamino]-propionic acid has been reported <92JCS(Pi)445>. 

Protection of amino groups. Amino acids are converted into p-tosylamino carbonyl derivatives by reaction with this isocyanate (20-807 yield). The derivatives are stable to dilute base and cold TFA. They are deblocked by hot ethanol/... 

The acid-catalysed rearrangement of two enantiomerically pure epoxides derived from sesquiterpenic himachalenes with Lewis and Brpnsted acids results in polycyclic compounds and mechanisms to explain the products have been proposed. Treatment of acyclic a-hydroxy and a-tosylamino sulflnyl dienes with amines gives enantiopure 1,4-diol or 1,4-hydroxysulfonamide derivatives.This one-pot proce- (g) dure entails a conjugate addition that triggers a diastereoselective sulfoxide-sulfenate [2,3]-sigmatropic rearrangement (Scheme 61). 

Earlier work on the s mthesis of chiral a-hydroxyaldehydes (see Vol. 21, p. 174 and Vol. 20, p.270) from d-mannitol-derived diepoxides has been extended to the synthesis of methyl (i )- and (S)-9-hydroxyeicosatetraenoates (methyl 9R-and 9S-HETE), and to coriolic acid [13(S)-hydroxy-9Z,llE-octadecadienoic acid] and its 13(S)-N-tosylamino-analogue. made from a bis-aziridine (Vol. 20, p.271). 8... 

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