112083-63-3

Usage

Uses

Used in Inorganic Synthesis:
ETHYL (S)-3,4-EPOXYBUTANOATE is used as a starting material for condensation reactions in inorganic synthesis. Its epoxybutanoate structure allows for versatile chemical transformations, making it a valuable component in the synthesis of various compounds.
Used in Organic Synthesis:
ETHYL (S)-3,4-EPOXYBUTANOATE is used as a precursor for the synthesis of homoallylic alcohol. The regiospecific ring opening of ETHYL (S)-3,4-EPOXYBUTANOATE with the cuprate derived from vinylmagnesium bromide and copper bromide-dimethyl sulfide complex results in a high yield (88%) of homoallylic alcohol, which is an important building block in organic chemistry.

Hazard

Causes skin irritation. Causes serious eye irritation. May cause respiratory irritation.

storage

Air Sensitive. Store in cool place. Keep container tightly closed in a dry and well-ventilated place. Store away from strong oxidizing agents, excess heat, air. Store at 2-8°C.

InChI:InChI=1/C6H10O3/c1-2-8-6(7)3-5-4-9-5/h5H,2-4H2,1H3/t5-/m1/s1

Upstream product

• 130158-22-4 ethyl (S)-3-((tert-butyldimethylsilyl)oxy)-4-iodobutanoate 
• 112100-39-7 (S)-4-iodo-3-hydroxy-butyric acid ethyl ester 
• 32223-97-5 (+/-)-ethyl-3,4-epoxybutanoate 
• 10488-69-4 ethyl (S)-4-chloro-3-hydroxybutanoate 

Downstream Products

• 151763-75-6 (R)-3-hydroxytetradecanoic acid ethyl ester 
• 2305-25-1 ethyl (R)-3-hydroxyhexanoate 
• 141942-85-0 (R)-ethyl 4-cyano-3-hydroxybutyrate 
• 118856-11-4 (R)-(-)-Ethyl 3-hydroxy-4-phenylbutanoate 

Relevant academic research and scientific papers

Diacyltransferase Activity and Chain Length Specificity of Mycobacterium tuberculosis PapA5 in the Synthesis of Alkyl β-Diol Lipids

Although they are classified as Gram-positive bacteria, Corynebacterineae possess an asymmetric outer membrane that imparts structural and thereby physiological similarity to more distantly related Gram-negative bacteria. Like lipopolysaccharide in Gram-negative bacteria, lipids in the outer membrane of Corynebacterineae have been associated with the virulence of pathogenic species such as Mycobacterium tuberculosis (Mtb). For example, Mtb strains that lack long, branched-chain alkyl esters known as dimycocerosates (DIMs) are significantly attenuated in model infections. The resultant interest in the biosynthetic pathway of these unusual virulence factors has led to the elucidation of many of the steps leading to the final esterification of the alkyl β-diol, phthiocerol, with branched-chain fatty acids known as mycocerosates. PapA5 is an acyltransferase implicated in these final reactions. Here, we show that PapA5 is indeed the terminal enzyme in DIM biosynthesis by demonstrating its dual esterification activity and chain-length preference using synthetic alkyl β-diol substrate analogues. By applying these analogues to a series of PapA5 mutants, we also revise a model for the substrate binding within PapA5. Finally, we demonstrate that the Mtb Ser/Thr kinases PknB and PknE modify PapA5 on three overlapping Thr residues and that a fourth Thr is unique to PknE phosphorylation. These results clarify the DIM biosynthetic pathway and indicate post-translational modifications that warrant further elucidation for their roles in the regulation of DIM biosynthesis.

An efficient synthesis of (R)-3-hydroxytetradecanoic acid

A short, efficient synthesis of (R)-3-hydroxytetradecanoic acid, a key component of bacterial endotoxins, using (R)-oxirane acetic acid ethyl ester as the source of chirality is described. The method is general and can be used in the preparation of other chiral 3-hydroxy acids.

Total synthesis of neopeltolide and analogs

Neopeltolide, a potent cytotoxin from a Carribean sponge, was synthesized through a brief sequence that highlights the use of ethers as oxocarbenium ion precursors. Other key steps include an acid-mediated etherification and sequence that features a Sonogashira reaction, an intramolecular alkyne hydrosilylation reaction, and a Tamao oxidation. The alkene that is required for the oxidative cyclization can be hydrogenated to provide access to the natural product or an epimer, or can be epoxidized or dihydroxylated to form polar analogs.

A Concise Stereoselective Total Synthesis of Methoxyl Citreochlorols and Their Structural Revisions

A concise, stereoselective and protecting group free approaches for the total synthesis of (?)-(2S,4R)- and (+)-(2R,4S)-3′-methoxyl citreochlorols and their stereoisomers are demonstrated. All four stereoisomers were synthesized to establish the absolute stereochemistry of the reported structures and the structures were revised accordingly. The approach involves chelation controlled regioselective reduction of a diester, silyl iodide promoted ring-opening iodo esterification of lactones, highly chemo- and regioselective ring-opening of an epoxy ester, dichloromethylation of a carboxyl group, and syn- and anti-selective reduction of the resulted β-hydroxy ketone as key steps.

Study of Class i and Class III Polyhydroxyalkanoate (PHA) Synthases with Substrates Containing a Modified Side Chain

Polyhydroxyalkanoates (PHAs) are carbon and energy storage polymers produced by a variety of microbial organisms under nutrient-limited conditions. They have been considered as an environmentally friendly alternative to oil-based plastics due to their renewability, versatility, and biodegradability. PHA synthase (PhaC) plays a central role in PHA biosynthesis, in which its activity and substrate specificity are major factors in determining the productivity and properties of the produced polymers. However, the effects of modifying the substrate side chain are not well understood because of the difficulty to accessing the desired analogues. In this report, a series of 3-(R)-hydroxyacyl coenzyme A (HACoA) analogues were synthesized and tested with class I synthases from Chromobacterium sp. USM2 (PhaCCs and A479S-PhaCCs) and Caulobacter crescentus (PhaCCc) as well as class III synthase from Allochromatium vinosum (PhaECAv). It was found that, while different PHA synthases displayed distinct preference with regard to the length of the alkyl side chains, they could withstand moderate side chain modifications such as terminal unsaturated bonds and the azide group. Specifically, the specific activity of PhaCCs toward propynyl analogue (HHxyCoA) was only 5-fold less than that toward the classical substrate HBCoA. The catalytic efficiency (kcat/Km) of PhaECAv toward azide analogue (HABCoA) was determined to be 2.86 × 105 M-1 s-1, which was 6.2% of the value of HBCoA (4.62 × 106 M-1 s-1) measured in the presence of bovine serum albumin (BSA). These side chain modifications may be employed to introduce new material functions to PHAs as well as to study PHA biogenesis via click-chemistry, in which the latter remains unknown and is important for metabolic engineering to produce PHAs economically.

SYNTHETIC DERIVATIVES OF MPL AND USES THEREOF

In one aspect, the present disclosure provides compounds of formulae (I) and (II). In another aspect, a compound of formula (I) or (II) is formulated into compositions with an antigen, optionally with a vesicle. In some embodiments, compositions are administered intramuscularly.

Synthesis of ethyl (R)-4-cyano-3-hydroxybutyrate in high concentration using a novel halohydrin dehalogenase HHDH-PL from Parvibaculum lavamentivorans DS-1

We identified and characterized a novel halohydrin dehalogenase HHDH-PL from Parvibaculum lavamentivorans DS-1. Study of substrate specificity indicated that HHDH-PL possessed a high activity toward ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE). After optimizations of the pH and temperature, whole cell catalysis of HHDH-PL was applied to the synthesis of ethyl (R)-4-cyano-3-hydroxybutyrate (HN) at 200 g L-1 of (S)-CHBE, which gave 95% conversion and 85% yield in 14 h.

Biocatalytic and Structural Properties of a Highly Engineered Halohydrin Dehalogenase

Two highly engineered halohydrin dehalogenase variants were characterized in terms of their performance in dehalogenation and epoxide cyanolysis reactions. Both enzyme variants outperformed the wild-type enzyme in the cyanolysis of ethyl (S)-3,4-epoxybutyrate, a conversion yielding ethyl (R)-4-cyano-3-hydroxybutyrate, an important chiral building block for statin synthesis. One of the enzyme variants, HheC2360, displayed catalytic rates for this cyanolysis reaction enhanced up to tenfold. Furthermore, the enantioselectivity of this variant was the opposite of that of the wild-type enzyme, both for dehalogenation and for cyanolysis reactions. The 37-fold mutant HheC2360 showed an increase in thermal stability of 8°C relative to the wild-type enzyme. Crystal structures of this enzyme were elucidated with chloride and ethyl (S)-3,4-epoxybutyrate or with ethyl (R)-4-cyano-3-hydroxybutyrate bound in the active site. The observed increase in temperature stability was explained in terms of a substantial increase in buried surface area relative to the wild-type HheC, together with enhanced interfacial interactions between the subunits that form the tetramer. The structures also revealed that the substrate binding pocket was modified both by substitutions and by backbone movements in loops surrounding the active site. The observed changes in the mutant structures are partly governed by coupled mutations, some of which are necessary to remove steric clashes or to allow backbone movements to occur. The importance of interactions between substitutions suggests that efficient directed evolution strategies should allow for compensating and synergistic mutations during library design.

NEW CHIRAL SALEN CATALYSTS AND METHODS FOR THE PREPARATION OF CHIRAL COMPOUNDS FROM RACEMIC EPOXIDES BY USING THEM

The present invention relates to new chiral salen catalysts and the preparation method of chiral compounds from racemic epoxides using the same. More specifically, it relates to new chiral salen catalysts that have high catalytic activity due to new molecular structures and have no or little racemization of the generated target chiral compounds even after the reaction is completed and can be also reused without catalyst regeneration treatment, and its economical preparation method to mass manufacture chiral compounds of high optical purity, which can be used as raw materials for chiral food additives, chiral drugs, or chiral crop protection agents, etc., using the new chiral salen catalysts.

Enantioselective entry to the Homalium alkaloid hoprominol: Synthesis of an (R,R,R)-hoprominol derivative

The diastereoselective synthesis of the N- and O-protected hoprominol derivative (R,R,R)-6 is described. The building up of the bicyclic O-silylated and di(N-tosylated) asymmetric scaffold 6 succeeded by convergent preparation of the two basic chiral azalactam units 7a and 7b and their subsequent iterative linking by a known method (Scheme 5). Both 4-alkyl-hexahydro-1,5-diazocin-2(1H)-ones 7a and 7b were prepared from the chiral β-amino acid portions 10a and 10b, respectively, by application of a set of reactions (e.g., N-alkylation of 10a,b and Sb(OEt)3-assisted cyclization of the resulting open-chain intermediates) already known. In comparison with the total syntheses of homaline (1) and homoprine (2), the newness of the described synthesis lies in the asymmetric approach to the difunctionalized fatty acid derivative 10b starting from (-)-(S)-malic acid (9) (Schemes 3 and 4). Key step in the preparation of 10b was the diastereoselective amination of the optically pure α,β-unsaturated δ-hydroxy homoallylic ester 14 via conjugate intramolecular aza-Michael cyclization of the acylic δ-(carbamoyloxy) intermediate 11.