79516-59-9

Upstream product

• 62959-96-0 (S)-(-)-hex-5-en-3-ol 
• 54074-85-0 ethyl-3-hydroxypentanoate 
• 141-82-2 malonic acid 
• 123-38-6 propionaldehyde 
• 94953-76-1 lithium α-lithioacetate 
• 10191-25-0 3-oxo-valeric acid 
• 13635-05-7 3-hydroxyvaleronitrile 
• 1372762-98-5 C₉H₁₇NO₃S 
• 64074-05-1 2,2-dimethyl-5-propanoyl-1,3-dioxan-4,6-dione 
• 437614-61-4 3-oxopentanoyl-N-acetylcysteamine thioester 
• 5461-96-1 ammonium D-xylonate 
• 98269-11-5 (S)-3-Hydroxy-pentanoic acid (1R,4S)-3-[benzenesulfonyl-(3,5-dimethyl-phenyl)-amino]-1,7,7-trimethyl-bicyclo[2.2.1]hept-2-yl ester 
• 82805-10-5 2,5-dibromo-2,5-dideoxy-D-lyxono-1,4-lactone 
• 42558-50-9 methyl (S)-3-hydroxyvalerate 

Downstream Products

• 10191-25-0 3-oxo-valeric acid 
• 137151-97-4 (2R,5R)-2,5-diisopropyl-1-phenylphospholane 
• 136705-66-3 (3S,6S)-octane-3,6-diol 
• 129705-30-2 (3S,6S)-3,6-dihydroxy-2,7-dimethyloctane 
• 124-38-9 carbon dioxide 
• 7732-18-5 water 
• 802294-64-0 propionic acid 
• 626-98-2 pent-2-enoic acid 
• 5204-64-8 3-pentenoic acid 

Relevant academic research and scientific papers

General chemoenzymatic route to two-stereocenter triketides employing assembly line ketoreductases

Modular polyketide synthases (PKSs) are enzymatic assembly lines that fuse carbon fragments into complex chiral products. Here, their synthetic logic is employed to chemoenzymatically generate two-stereocenter triketides. Each of the four stereoisomers was constructed in a stereocontrolled manner using C-acylation and two PKS ketoreductases possessing opposite stereoselectivities.

Stereochemical Consequences of Vinylpyruvate Hydratase-Catalyzed Reactions

A stereochemical analysis has been carried out on two vinylpyruvate hydratases (VPH), which convert 2-hydroxy-2,4-pentadienoate to 2-keto-4S-hydroxypentanoate in meta-fission pathways. Bacterial strains with this pathway can use aromatic compounds as sole sources of energy and carbon. The analysis was carried out using the 5-methyl and 5-chloro derivatives of 2-hydroxy-2,4-pentadienoate with the enzymes from Pseudomonas putida mt-2 (Pp) and Leptothrix cholodnii SP-6 (Lc). In both organisms, VPH is in a complex with the preceding enzyme in the pathway, 4-oxalocrotonate decarboxylase (4-OD). In D2O, a deuteron is incorporated stereospecifically at the C-3 and C-5 positions of product by both Pp and Lc enzymes. Accordingly, the complexes generate (3S,5S)-3,5-[di-D]-2-keto-4S-hydroxyhexanoate and (3S,5R)-3,5-[di-D]-2-keto-4R-hydroxy-5-chloropentanoate (4R and 5R due to a priority numbering change). The substitution at C-5 (CH3 or Cl) or the source of the enzyme (Pp or Lc) does not change the stereochemical outcome. One mechanism that can account for the results is the ketonization of the 5-substituted dienol to the α,β-unsaturated ketone (placing a deuteron at C-5 in D2O), followed by the conjugate addition of water (placing a deuteron at C-3). The stereochemical outcome for VPH (from Pp and Lc) is the same as that reported for a related enzyme, 2-oxo-hept-4-ene-1,7-dioate hydratase, from Escherichia coli C. The combined observations suggest similar mechanisms for these three enzymes that could possibly be common to this group of enzymes.

Photolysis and photocatalysis of ibuprofen in aqueous medium: Characterization of by-products via liquid chromatography coupled to high-resolution mass spectrometry and assessment of their toxicities against Artemia Salina

The degradation of the pharmaceutical compound ibuprofen (IBP) in aqueous solution induced by direct photolysis (UV-A and UV-C radiation) and photocatalysis (TiO2/UV-A and TiO2/UV-C systems) was evaluated. Initially, we observed that whereas photocatalysis (both systems) and direct photolysis with UV-C radiation were able to cause an almost complete removal of IBP, the mineralization rates achieved for all the photodegradation processes were much smaller (the highest value being obtained for the TiO 2/UV-C system: 37.7%), even after an exposure time as long as 120 min. Chemical structures for the by-products formed under these oxidative conditions (11 of them were detected) were proposed based on the data from liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) analyses. Taking into account these results, an unprecedented route for the photodegradation of IBP could thus be proposed. Moreover, a fortunate result was achieved herein: tests against Artemia salina showed that the degradation products had no higher ecotoxicities than IBP, which possibly indicates that the photocatalytic (TiO2/UV-A and TiO2/UV-C systems) and photolytic (UV-C radiation) processes can be conveniently employed to deplete IBP in aqueous media. Copyright

A study of the reaction of n-BuLi with Ti(Oi-Pr)4 as a method to generate titanacyclopropane and titanacyclopropene species

The use of the combination of reagents Ti(Oi-Pr)4/n-BuLi, introduced by the group of J.J. Eisch in 2001, has only found a few applications so far, with sometimes conflicting observations. This article describes a study aimed at clarifying the nature, the stability and the reactivity of the active organometallic species involved. Reactions with CO2 and other trapping reagents reveal that it is generated within a few minutes at 0 C in THF, where it can be considered to be stable for 30 min. Most of our results are consistent with the expected titanacyclopropane nature of this reagent but some observations suggest that the chemistry at play may be more complicated.

PHA E and PHA C components of poly(hydroxy fatty acid) synthase from thiocapsa pfennigii

PCT No. PCT/DE95/01279 Sec. 371 Date Jul. 3, 1997 Sec. 102(e) Date Jul. 3, 1997 PCT Filed Sep. 15, 1995 PCT Pub. No. WO96/08566 PCT Pub. Date Mar. 21, 1996The present invention relates to a process for the production of poly (hydroxy fatty acids) as well as recombinant bacterial strains for carrying out the process. In addition, new poly(hydroxy fatty acids) and new substrates for the production of conventional and new poly(hydroxy fatty acids) are described. Moreover, the invention also relates to a DNA fragment, which codes for a PhaE and a PhaC component of the poly(hydroxy fatty acid) synthase from Thiocapsa pfennigii, as well as the corresponding poly (hydroxy fatty acid) synthase protein.

New chiral phospholanes; synthesis, characterization, and use in asymmetric hydrogenation reactions

We describe the practical synthesis of enantiomerically pure trans-2,5-disubstituted-1-phenylphospholanes which are then employed in the preparation of a new series of C2-symmetric bis- and C3-symmetric tris(phospholane) ligands. A versatile three-step route to the important chiral 1,4-diol intermediates, used in the phosphine syntheses, is outlined. Rhodium complexes bearing the new phosphine ligands were prepared and shown to act as efficient catalyst precursors for the enantioselective hydrogenation of various unsaturated substrates.

Asymmetric Reduction of Aliphatic Short- to Long-Chain β-Keto Acids by Use of Fermenting Bakers' Yeast

Eleven β-keto acids, ranging from 3-oxobutanoic to 3-oxooctanoic acids, were reduced with fermenting bakers' yeast to the corresponding optically active β-hydroxy acids, which were isolated as the methyl esters.In all cases, the (R)-hydroxy acids were obtained in >/=98percent ee, except for 3-oxobutanoic acid, which afforded the (S)-hydroxy acid in 86percent ee.Inhibition of fermentation was observed for 3-oxoundecanoic to 3-oxotetradecanoic acids, leading to no reduction.Lowering of the substrate concentration was found to be appreciably effective in avoiding inhibition.

Process for production of N-acyl-α-amino acids

A process for the production of an N-acyl-α-amino acid represented by the general formula STR1 wherein R1, R2, R3 and R4, independently from each other, represent a hydrogen atom, an alkyl or cycloalkyl group which may be substituted, or an aryl or heteroaromatic group selected from the group consisting of furyl, pyrrolyl, pyridinyl, thienyl and indolyl which may be substituted, which comprises reacting an oxirane represented by the general formula STR2 wherein R1 and R2 are as defined above, an amide compound represented by the general formula wherein R3 and R4 are as defined above, and carbon monoxide in the presence of hydrogen, a cobalt-containing catalyst, and a promoter composed of a compound containing a metal selected from Groups I, II, III and IV of the periodic table.