Tryptophan hydantoin

Maeda and Yoshida 238, 239) by hydroformylation of acrolein obtained l,l-diacetoxy-4,4-dialkoxybutane (17), which by Buecherer s reaction gave (3-(hydanto-5-yl-)propionaldehyde acetal (18). The phenyl-hydrazone of (18), by the Fischer indole synthesis, gave tryptophan hydantoin (20). Attempts to obtain crystalline (20) were unsuccessful,... 

Tryptophane (10, 100) By condensation of indole-3-aldehyde with hydantoin in the presence of piperidine, followed by treatment of the product with ammonium sulfide and ammonium hydroxide at ioo° for 500 hours, Boyd and Robson, Biochem. J. ag, 2256 (1935). 

C iH FjNO, J254S3-3I-0) see Dolasetron mesilate indole-3-carboxylic acid imidazolide (CiiHoNjO 99445-26-S) see Tropisetron (S)-indoline-2-carboxylic acid (QjH.jNOj 79815-20-6) see Perindopril ( )-2-(lH-indol-5-yl)-A -methylethenesulfonamide (CiiHijNjOjS 98623-49-5) see Naratriptan 5-(3-indolylmcthyl)hydantoin (Ci2H N,02 21753-16-2) see L-Tryptophan... 

Condensation of formyl-pyrroles and -indoles with a wide range of other activated methylene compounds has been reported. These include, for example, hydantoin, which provides a useful synthetic route to tryptophane and j8- (pyrrolyl)alanines, thiohydantoin, rhodanine and AT-substituted barbituric acids (B-77MI30505, 79HC(25-3)357). Flash pyrolysis of the condensation product derived from 3-formyl-2,5-dimethylpyrrole with Meldrum s acid produces 6-hydroxy-2-methylindole, (440) — (441) (74AJC2605), whilst the analogous... 

Figure 12.14 Initial reaction rate for the production of different optically pure D-amino acids from 5-monosubstituted hydantoins using systems 1 and 2. TRP, D-tryptophan TYR, D-tyrosine pH PC, D-p-hydroxyphenyl glycine VAL, D-valine ...

In a few cases, alkaline hydrolysis has proved applicable to special problems. Tryptophan is not destroyed in alkali, and analysis of alkaline hydrolyzates forms the basis of one method for quantitative determination of this amino acid (e.g., Dreze, 1960). Despite the fact that tryptophan-containing peptides should be more stable in alkali than acid, partial alkaline hydrolysis has not been employed for identification of this type of peptide. Amino acids often can be regenerated by alkaline hydrolysis from derivatives obtained by the amino-terminal end-group methods. Dinitrophenyl amino acids and phenylthiohydantoin (Fraenkel-Conrat et al., 1955) as well as hydantoin (Stark and Smyth, 1963) derivatives of amino acids can be treated in this manner. 

D-p-Hydroxyphenyl glycine is a key raw material for the semisynthetic penicillins such as ampidllin and amoxycillin. It is also used in photographic developers. Racemic hydantoins are synthesized starting from phenol derivatives, glyoxylic acid and urea via the Mannich condensation (Fig. 19-28). The D-specific hydantoinase is applied as immobilized whole cells in a batch reactor. The unreacted L-hydantoins are readily racemized under the alkaline conditions (pH 8) of enzymatic hydrolysis, yielding quantitative conversion. This process enables the stereospecific preparation of various amino acids, such as L-tryptophane, L-phenylalanine, D-valine, D-alanine... 

Benzo[b]thiophene analogs 111 (R1 = H, 5- or 6-R2) of substituted tryptophans have been prepared by reaction of a 5- or 6-substituted 3-chloromethylbenzo[i>]thiophene with diethyl acetamido- or formamido-malonate, and hydrolysis of the product.456,472,473 Corresponding a-methyl derivatives (111, R1 = Me) may be obtained by the hydantoin route (Eq. 3).47 2... 

Tryptophan is obtained industrially by a variation of the Fischer indole synthesis. Addition of hydrogen cyanide to acrolein gives 3-cyano-propanal which is converted to hydantoin through a Bucherer reaction. The nitrile group is then... 

Sun et al. [52] have developed IL-supported green strategy for the synthesis of oxo- and thio-hydantoin moieties attached with tetrahydro-/3-carboline in aqueous media under microwave irradiation (Scheme 15) [52]. Boc-protected L-tryptophan 124 was anchored on 1 by esterification method to give IL-bound tryptophan 125 (Scheme 15). IL-attached tryptophan 125 tmderwent a Boc deprotection followed by Pictet-Spengler cyclization with... 

Similar reactions transform DL-5-monosubstituted hydantoins to L-amino acids. Yo-kozeki et al. [11] analyzed the reaction mechanism of L-tryptophan production from dl-5-(3 -indolylmethyl)hydantoin by Flavobacterium sp. and found that nonstereospecific hydrolysis of hydantoin derivative and the L-sj ific hydrolysis of racemic A-carbamoyl amino acid were involved in this transformation. Yamashiro et al. [12] found the L-specific hydrolysis of a hydantoin derivative in L-valine production firom DL-5-isopropylhydantoin by Bacillus sp. and that ATP was absolutely required for this amidohydrolytic reaction. 

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