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Butyrolactone, hydroxy

Muricatacin 19 (5-hydroxyheptadecan-4-olide) was isolated from Annona muricata (11) as a mixture of (+) and (-) muricatacin with a slight excess of the (-)-enantiomer (4R, 5R) and it is supposed to be a natural (or unnatural) metabolite of acetogenins. It has been shown tha this hydroxy-butyrolactone presents some in vitro cytotoxicity (11). Since its isolation in 1991, many syntheses have been reported in the literature and are discussed herein. [Pg.213]

Triol 984 is converted to acetonide 985 and the free hydroxyl group is sequentially oxidized to an aldehyde (986) with pyridinium chlorochromate and then to an acid under Jones conditions. Acidic workup furnishes the hydroxy butyrolactone 987. Treatment of THP-protected butyrolactone 988 with methyl Grignard reagent affords diol 989. Removal of the THP group, tosylation of the primary alcohol, and cyclization under basic conditions provides epoxide 990. Opening the oxirane ring with 2-(l,3-butadienyl)magnesium chloride in the presence of... [Pg.286]

Sp th and Platzer (27) subsequently described a simpler synthesis of the alkaloid, by condensing o-aminobensylamine with ot-hydroxy-butyrolactone (XX) with butyrolactone itself, peg-9-en (desoigrvasicine) (VII) was obtained. [Pg.109]

Supplement (combined with Volumes XVIII and XIX) XVII, 2nd 1934 2359-3031 Hydroxy compounds Furfuryl alcohol, 112. Carbonyl compounds Butyrolactone, 234. Furfural, 272. 2-Aoetyl-thio-phene, 287. Xanfhone, 366. Succinic anhydride, 404. Phthalio anhydride, 469. [Pg.1123]

The 4-hydroxy-1-alkene (homoallylic alcohol) 81 is oxidized to the hetni-acetal 82 of the aldehyde by the participation of the OH group when there is a substituent at C3. In the absence of the substituent, a ketone is obtained. The hemiacetal is converted into butyrolactone 83[117], When Pd nitro complex is used as a catalyst in /-BuOH under oxygen, acetals are obtained from homoallylic alcohols even in the absence of a substituent at C-3[l 18], /-Allylamine is oxidized to the acetal 84 of the aldehyde selectively by participation of the amino group[l 19],... [Pg.33]

Butyrolactones are prepared by intramolecular reaction of haloallylic 2-alkynoates. The a-chloromethylenebutyrolactone 301 is prepared by the intramolecular reaction of300[150,151]. 4 -Hydroxy-2 -alkenyl 2-alkynoates can be used instead of haloallylic 2-alkynoates, and in this reaction, Pd(II) is regenerated by elimination of the hydroxy group[152]. As a related reaction, the q-(chloromethylene)-7-butyrolactone 304 is obtained from the cinnamyl 2-alkynoate 302 in the presence of LiCl and CuCbflSS]. Isohinokinin (305) has been synthesized by this reaction[l 54]. The reaction is explained by chloro-palladation of the triple bond, followed by intramolecular alkene insertion to generate the alkylpalladium chloride 303. Then PdCb is regenerated by attack of CuCb on the alkylpalladium bond as a key step in the catalytic reaction. [Pg.505]

Apart from lactic and hydroxyacetic acids, other a- and P-hydroxy acids have been small-volume specialty products produced in a variety of methods for specialized uses. y-Butyrolactone [96 8-0] which is the monomeric inner ester of y-hydroxybutyric acid [591-81-17, is a large-volume chemical derived from 1,4-butanediol (see Acetylene-derived chemicals). [Pg.517]

Other methods include ring opening of parasorbic acid [108-54-3] (5-lactone of 5-hydroxy-2-hexenoic acid) in hydrochloric acid or in alkaline solutions (43,44), the ring opening of y-vinyl- y-butyrolactone in various catalysts (45,46), or isomerization of 2,5-hexadienoic acid esters (47,48). Other methods are described in thehterature (6,49,50). [Pg.284]

Chemically, wood tar is a complex mixture that contains at least 200 individual compounds, among which the foUowing have been isolated (1) 2-methoxyphenol, 2-methoxy-4-ethylphenol, 5-meth5i-2-methoxyphenol, 2,6-x5ienol, butyric acid, crotonic acid, 1-hydroxy-2-propanone, butyrolactone, 2-methyl-3-hydroxy-4JT-pyran-4-one, 2-methyl-2-propenal, methyl ethyl ketone, methyl isopropyl ketone, methyl furyl ketone, and 2-hydroxy-3-methyl-2-cyclopenten-l-one. [Pg.335]

Hydroxy-3,3-dimethyl-y-butyrolactone (3-hydroxy-4,4-dimethyl-4,5-dihydrofuran-... [Pg.542]

Recently, it was found that the addition of benzylamine to 2-(5//)-furano-3-ylmethanesulfonate 280 (X = O—SOaMe) in methanol afforded a 7 1 mixture of the trans- and cw-methyl-A-benzyl-2-hydroxymethylaziridine-2-carboxylates 281 and 282, respectively (00TL3061). Treatment of 281 with benzyl alcohol in the presence of BF3 OEta furnished, after hydrolysis, rac-cw-amino-a-hydroxy-/3-butyrolactone 284 (Scheme 74). [Pg.154]

The synthesis of 4-alkyl-y-butyrolactones 13 and 5-alkyl-<5-valerolactones 14 can be achieved in high enantiomeric excess by alkylation of ethyl 4-oxobutanoate and ethyl 5-oxopentanoate (11, n = 2, 3). The addition of diethylzinc, as well as dimethylzinc, leads to hydroxy esters 12 in high optical purity. When methyl esters instead of ethyl esters are used as substrates, the enantioselectivity of the addition reaction is somewhat lower. Alkaline hydrolysis of the hydroxy esters 12, followed by spontaneous cyclization upon acidification, leads to the corresponding y-butyro- and -valerolactones32. [Pg.181]

Centers for Disease Control and Prevention Gamma hydroxy butyrate use—New York and Texas, 1995-96. JAMA 277 1511, 1997 Centers for Disease Control and Prevention Adverse events associated with ingestion of gamma-butyrolactone—Minnesota, New Mexico, and Texas, 1998-1999. MMRW Morb Mortal Wkly Rep 48 137-140, 1999 Chatlos JC Recent trends and a developmental approach to substance abuse in adolescents. Child Adolesc Psychiatr Clin N Am 5 1-27, 1996... [Pg.261]

Further examples of the utility of the allylic sulfoxide-sulfenate interconversion in the construction of various biologically active natural products include intermediates such as the jg-hydroxy-a-methylene-y-butyrolactones (e.g. 63) and tetrahydrochromanone derivative 64. Interestingly, the facility and efficiency of this rearrangement has also attracted attention beyond the conventional boundaries of organic chemistry. Thus, a study on mechanism-based enzyme inactivation using an allyl sulfoxide-sulfenate rearrangement has also been published... [Pg.733]

Moreover, Kim and coworkers have shown that a-amino-butyrolactones can be synthesized by a related process employing the amino acid homoserine with an unprotected hydroxy functionality [31]. In a more recent publication by the same research group, morpholin-2-one derivatives of type 9-37 have been prepared (Scheme 9.6) [32]. Herein, glycolaldehyde dimer 9-32 acts as a bifunctional compound, which first reacts with the a-amino acids 9-33 to give the iminium ions 9-34,... [Pg.546]

Lithiated chiral oxazolines have been shown to react with various electrophiles, generating a new asymmetric center with considerable bias. This process has led to the synthesis of optically active a-alkylalkanoic acids,47 n-hydroxy(methoxy)alkanoic acids,48 / -hydroxy(methoxy)alkanoic acids,49 n-substituted y-butyrolactones,50 and 2-substituted-l,4-butanediols (Fig. 2-4).50... [Pg.92]

Hydroxy-y-butyrolactone, 46, 24 4-Hydroxycrotononitrile, by-product in preparation of 3-hydroxyglutaro-nitrile, 46, 49... [Pg.76]

An obvious way to target chiral compounds is to start with a compound in which the chiral center is already present. Here natural products and derivatives offer a rich pool of generally inexpensive starting materials. Examples include L-hydroxy and amino adds. Sometimes, just one out of many chiral centers is predestined to remain, as in the synthesis of vitamin C from D-glucose, or in the preparation of (S)-3-hydroxy-y-butyrolactone from ladose. [Pg.113]

Chiral butyrolactones of type 27 and 28 have substantial value in asymmetric synthesis because they contain readily differentiable difunctional group relationships e.g. 1,5-di-carboxylic acid, 1,4-hydroxy carboxylic acid, 1,6-hydroxy-carboxylic acid, 1,6-diol etc.) that would be difficult to assemble by existing asymmetric condensation and pericyclic processes. Applications of these chiral derivatives of glutaric acid to syntheses of indole, indoline and quinolinone alkaloids are illustrated in Schemes 16-18. [Pg.4]

The original preparation of y-crotonolactone by Lespieau involved a five-step sequence from epichlorohydrin and sodium cyanide. A recent detailed study of this procedure reported an overall yield of 25% for the lactone. Glattfeld used a shorter route from glycerol chlorohydrin and sodium cyanide hydrolysis and distillation of the intermediate dihydroxy acid yielded y-cro-tonolactone in 23% yield and -hydroxy-y-butyrolactone in 28% yield. The formation of y-crotonolactone in 15% yield has also been reported from pyrolysis of 2,5-diacetoxy-2,5-dihydrofuran at 480-500 . ... [Pg.13]

Block copolymers of (R,S)-(3-butyrolactone and eCL have been synthesized by combining the anionic ROP of the first monomer with the coordinative ROP of the second one (Scheme 15) [71]. The first step consisted of the synthesis of hydroxy-terminated atactic P(3BL by anionic polymerization initiated by the alkali-metal salt of a hydroxycarboxylic acid complexed with a crown ether. The hydroxyl end group of P(3BL could then be reacted with AlEt3 to form a macroinitiator for the eCL ROP. [Pg.24]

Both, a-hydroxylated lignans of the dibenzyllactone-type and of the biarylcyclooctane-type have been enantioselectively prepared from the corresponding / -benzyl-y-butyrolactones via a-alkylation followed by a-oxy-genation (Scheme 5). The hydroxy group was introduced in two different... [Pg.191]

A more useful way of reducing esters to ethers is a two-step procedure applied to the reduction of lactones to cyclic ethers. First the lactone is treated with diisobutylaluminum hydride in toluene at —78°, and the product - a lactol - is subjected to the action of triethylsilane and boron trifluoride etherate at —20° to —70°. y-Phenyl-y-butyrolactone was thus transformed to 2-phenyltetrahydrofuran in 75% yield, and 5-lactone of 3-methyl-5-phenyl-5-hydroxy-2-pentenoic acid to 4-methyl-2-phenyl-2,3-dihydropyran in 72% yield [1034]. [Pg.150]

Pyrano-fused heterocycles, namely pyrano[3,2-f]quinoline-2,5(6//)-diones, pyrano[3,2-f]benzopyran-2,5(6//)-dione, and pyrano[3,2-f]pyridine-2,5(67T)-diones, have been efficiently prepared by the condensation of 4-hydroxy-2-(l//)-quinolines, 4-hydroxycoumarin, or 4-hydroxy-(17/)-pyridone with a-acetyl-y-butyrolactone or the sodium salt of a-formyl-y-butyro-lactone in the presence of ammonium acetate <1999JHC467>. [Pg.729]


See other pages where Butyrolactone, hydroxy is mentioned: [Pg.619]    [Pg.810]    [Pg.21]    [Pg.171]    [Pg.26]    [Pg.130]    [Pg.733]    [Pg.260]    [Pg.131]    [Pg.143]    [Pg.172]    [Pg.1177]    [Pg.459]    [Pg.421]    [Pg.193]    [Pg.213]    [Pg.119]    [Pg.73]    [Pg.140]    [Pg.336]    [Pg.45]    [Pg.48]    [Pg.208]    [Pg.127]    [Pg.443]    [Pg.496]   
See also in sourсe #XX -- [ Pg.24 , Pg.46 ]




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