Amino-y-butyrolactone

In addition, other systems of nomenclature for AHLs have also appeared in the literature describing them as derivatives of furanone, y-butyrolactone or 4-butanolide. For example, the above V.fischeri autoinducer can also be named as (S)-N-(3-oxohexanoyl)-3-aminodihydro-2(3H)-furanone,(S)-a-(3-oxohexa-noyl)amino-y-butyrolactone or (S)-2-(3-oxohexanoyl)amino-4-butanolide (another IUPAC name) [27]. 

Few accounts of the reactions of coordinated ligands have been published. One recent report indicates that the copper complex of S-methylmethionine yields the copper complex of a-amino-y-butyrolactone and dimethyl sulfide upon heating.8 ... 

Acetoxy-l-acetylproline, 251 L-a-Amino-y-butyrolactone, 207 /-Butyl hydroperoxide-Dialkyl tar-trate-Titanium(IV) isopropoxide, 51 (Camphorylsulfonyl)oxaziridines, 64 Cumene hydroperoxide-Dialkyl tar-trate-Titanium(IV) isopropoxide, 52 Diisobutylaluminum hydride-Tin(II) chloride-(S)-1 -[ 1 -Methyl-2-pyrroii-dinyl]methylpiperidine, 116 (S)-Phenylglycine, 225 L-Valine, 226 Crown ethers Benzo-14-crown-4, 143 12-Crown-4, 167 12-Crown-6, 218... 

Amino-y-butyrolactones.5 The (dimethylamino)carbene 1 undergoes highly diastereoselective aldol reactions with aldehydes even in the absence of a Lewis acid to form syn-adducts 2, from which the metal unit can be removed by photolysis. 

Radical addition-cyclization of substrate (115) bearing two different radical acceptor such as acrylate and aldoxime ether moieties generates (3-amino-y-butyrolactones (116a) and (116b) (eq. 4.40) [118-120],... 

Early syntheses of SeMet were tedious, non-stereospecific or limited to small-scale preparations. Klosterman and Painter (1947), for example, first reacted 5-((3-bromoethyI)- hydantoin with benzyl selenol to yield y-benzylselenoho-mocysteine. The latter was converted to the sodium salt of DL-selenohomo-cysteine with sodium in liquid ammonia, and reacted with methyl iodide to yield DL-SeMet. Plieninger (1950) obtained DL-SeMet by the reaction of sodium selenomethyl mercaptide with a-amino-y-butyrolactone in an inert solvent at 170°C. A synthesis of DL-SeMet from acrolein was also described (Zdansky, 1968). The first stereospecific synthesis of L-SeMet via esters of tosylated homoserine was reported by Pande et al. (1970). 

Plieninger, H. 1950. The cleavage of y-butyrolactone and a-amino-y-butyrolactone with sodium methylmercaptide or selenide. A synthesis of methionine. Chem. Ber. 83, 265-268. 

Amino-1,4 butanediol, 3-aminotetrahydrofuran, aspartic anhydride, amino-y-butyrolactone... 

Lactone 4-Aminodihydro-2 3H)-furanone. p-Amino-y-butyrolactone C4H7NO2 M 101.105... 

Method Four, Snyder et al, (736). ct-Oximino-y-bu rrolactone (A) u prepared in 90% yield from acetobutyro-y-l stone and ethyl nitrite in methanol. 3,6-Bis-(j8-hydroxyethyl)-2,5-diketopiperazine (B) is prepared in 60% yield from (A) through a-amino-y-butyrolactone by reduction of the oxime with hydrogen and a palladium catal3rst. 3,6-Bis-(j3-chloroethyl)-2,5-diketopiperazine (C) is prepared in 90% yield from (B) and thionyl chloride. 3,6-Bis-(j8-methylthiolethyl)-2, diketopiper-azine (D) is prepared in 60% yield from (C) and sodium methylmer-captide . DL-Methionine is prepared in 90% 3rield by the HCl hydrolyris of (D). The over-all yield is 26%. 

Prepared from phenoxyethyl bromide (559) and malonic ester by the procedure of Fischer and Blumenthal (293). o-Amino-y-butyrolactone hydrochloride has been prepared from y-butyrolactone through the o-bromo-y-butyrolactone lavak et cl. (521), by reduction of crroximino> y-but3rrolaotone with tin and HCl (450) or with Baney Nickel and hydrogen (450). The intermediate o-acetamino-y-butyrolactone was hydrolysed by the method of Hill and Robson (400). 

The direct cleavage of Ado-Met into the thioether and a-amino-y-butyrolactone, which is then converted non-enzymatically into homoserine, is catalyzed by a lyase distributed in prokaryotes and eukaryotesl (pathway 2). 

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