51756-07-1

Upstream product

• 67-56-1 methanol 
• 764-85-2 Nonanoyl chloride 
• 111-79-5 methyl 2-nonenoate 
• 110-53-2 1-Bromopentane 
• 105-45-3 acetoacetic acid methyl ester 
• 2033-24-1 cycl-isopropylidene malonate 
• 2528-61-2 Heptanoic acid chloride 
• 331672-95-8 1H-1,2,3-benzotriazol-1-yl(n-hexyl)methanone 
• 111-14-8 oenanthic acid 
• 38330-80-2 monomethyl monopotassium malonate 
• 66696-80-8 heptanoyl Meldrum s acid 
• 186581-53-3 diazomethane 
• 1007476-32-5 sodium ethyl acetylacetate enolate 

Downstream Products

• 40435-57-2 3-oxononanoic acid 
• 111-14-8 oenanthic acid 
• 145401-48-5 sphingofungin F 
• 78009-99-1 7-(2-n-hexyl-1,3-dioxolan-2-yl)-n-heptyl-triphenylphosphonium bromide 

Relevant academic research and scientific papers

Determination of the Absolute Configurations and Sensory Properties of the Enantiomers of a Homologous Series (C6-C10) of 2-Mercapto-4-alkanones

The enantiomers of a homologous series (C6-C10) of 2-mercapto-4-alkanones were obtained by lipase-catalyzed kinetic resolution of the corresponding racemic 2-acetylthio-4-alkanones. Their configurations were assigned via vibrational circular dichroism and 1H NMR anisotropy based methods. Odor thresholds and odor qualities were determined by capillary gas chromatography-olfactometry using chiral stationary phases. There were minima of the odor thresholds for the chain lengths C7 and C8. Except for chain length C8, the enantiomers of the other homologues showed similar odor thresholds. The odor qualities ranged from pungent (C5) to mushroom (C9 and C10) and were similar to those known for the corresponding 1-alken-3-ones with one less C atom. In contrast to their positional isomers (4-mercapto-2-alkanones), the investigated 2-mercapto-4-alkanones do not meet the requirements of a "tropical olfactophore" (i.e., compounds possessing a 1,3-oxygen-sulfur functionality and specific arrangements of the substituents).

Isolation of the antibiotic pseudopyronine B and SAR evaluation of C3/C6 alkyl analogs

Natural products are an abundant source of structurally diverse compounds with antibacterial activity that can be used to develop new and potent antibiotics. One such class of natural products is the pseudopyronines. Here we present the isolation of pseudopyronine B (2) from a Pseudomonas species found in garden soil in Western North Carolina, and SAR evaluation of C3 and C6 alkyl analogs of the natural product for antibacterial activity against Gram-positive and Gram-negative bacteria. We found a direct relationship between antibacterial activity and C3/C6 alkyl chain length. For inhibition of Gram-positive bacteria, alkyl chain lengths between 6 and 7 carbons were found to be the most active (IC50?=?0.04–3.8?μg/mL) whereas short alkyl chain analogs showed modest activity against Gram-negative bacteria (IC50?=?223–304?μg/mL). This demonstrates the potential for this class of natural products to be optimized for selective activity against either Gram-positive or Gram-negative bacteria.

Discovery of a potent nicotinic acid receptor agonist for the treatment of dyslipidemia

Nicotinic acid has been used clinically for decades to control serum lipoproteins. Nicotinic acid lowers very low-density lipoprotein (VLDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, and lipoprotein-a (LPa), and it is also effective in raising high-density lipoprotein (HDL)-cholesterol. However, nicotinic acid has several side effects in clinical use. The most notable is intense cutaneous vasodilation "flushing"+ on the upper body and face. We discovered a pyranopyrimidinedione series to be nicotinic acid receptor agonists. A potent nicotinic acid receptor agonist from this series {5-(3-cyclopropylpropyl)-2-(difluoromethyl)-3H-pyrano[2,3-d] pyrimidine-4,7-dione}with reduced flushing side effect in dogs was identified.

Biomimetic synthesis of a new class of bacterial signaling molecules

The first synthesis of a newly discovered class of bacterial signaling molecules from Streptomyces coelicolor has been developed. These molecules, known as the methylenomycin furans (MMFs), trigger production of the antibiotic methylenomycin. The synthesis features a scandium triflatecatalyzed domino reaction of β-ketoesters and dihydroxyacetone yielding 2,3,4-substituted furans. The proposed reaction sequence (aldol reaction, cyclization, and dehydrative aromatization) may be reminiscent of the biosynthetic reaction in which dihydroxyacetone phosphate and a β-ketothioester are condensed by an enzyme.

Substitution of acyl for acetyl with N-acylbenzotriazoles catalyzed by samarium triiodide

Catalyzed by samarium triiodide (SmI3), substitution of acyl with N-acylbenzotriazoles for acetyl in acetoacetic esters and acetylacetone proceeds smoothly under neutral conditions in open air, affording the corresponding β-keto esters and β-diketones in good yields. Copyright Taylor & Francis Group, LLC.

Chemical synthesis of a glycolipid library by a solid-phase strategy allows elucidation of the structural specificity of immunostimulation by rhamnolipids

The first synthesis of a glycolipid library by hydrophobically assisted switching phase (HASP) synthesis is described. HASP synthesis enables flexible switching between solution-phase steps and solid-supported reactions conducted with molecules attached to a hydrophobic silica support. A library of glycolipids derived from the lead compound 1 - a strongly immunostimulatory rhamnolipid - with variations in the carbohydrate part, the lipid components, and the stereochemistry of the 3-hydroxy fatty acids was designed and synthesized. The enantiose lective synthesis of the 3-hydroxy fatty acid building blocks was achieved by employing asymmetric hydrogenation of 3-oxo fatty acids. Glycolipids were prepared by this approach without any intermediary isolation steps, mostly in excellent yields. Final deprotection to the carboxylic acids was accomplished by enzymatic ester cleavage. All prepared rhamnolipids were tested for their immunostimulatory properties against human monocyte cells by assaying the secretion of the cytokine tumor necrosis factor α (TNFα) into the medium. The observed structure-activity relationships of rhamnolipids indicate a specific, recognition-based mode of action, with small structural variations in the rhamnolipids resulting in strong effects on the immunostimulatory activities of the rhamnolipids at low micromolar concentrations.

Mild conversion of β-diketones and β-ketoesters to carboxylic acids

A mild protocol for the conversion of β-ketoesters and β-diketones to carboxylic acids with use of CAN in CH3CN is described. The method is compatible with a number of functional groups, and can generate carboxylic acids under neutral conditions at room temperature. The reaction is fast and general, providing an alternative method to the commonly used malonic ester acid preparation. Initial mechanistic studies show that initial oxidation of the enol form of the β-dicarbonyl initiates the reaction. The presence of nitrate as an oxidant ligand or as an additive is critical for success of the reaction.

Benzofurylpyrone derivatives

There is provided benzofuryl-α-pyrone derivative represented by the following structural formula (I): wherein R1represents a hydrogen atom or an alkyl group of 1 to 5 carbons; R2represents hydrogen, —CO—R5or —SO2/sub

Meerwein Saponification of Alkyl 3-Oxoalkanoates in the Gas Chromatograph

Alkyl 3-oxoalkanoates decompose by unevitable traces of water in the gas chromatograph to yield the corresponding methyl ketones and alcohols (Meerwein saponification).Decomposition occurs in the hot injector (T= 270 deg C) of the gas chromatograph and also on glass capillary columns (T> 160 deg C).Decomposition in routine work can be avoided by preparing the corresponding 3-trimethylsilyl enol ethers.

A NEW PREPARATIVE METHOD FOR 1,3-DICARBONYL COMPOUNDS BY THE REGIOSELECTIVE OXIDATION OF α,β-UNSATURATED CARBONYL COMPOUNDS, CATALYZED BY PdCl2 USING HYDROGENPEROXIDES AS THE REOXIDANT OF Pd0

α,β-Unsaturated esters and ketones are oxidized regioselectively to give β-keto esters and 1,3-diketones in good yields in aqueous acetic acid using Na2PdCl4 as the catalyst and t-butyl hydroperoxide or hydrogen peroxide as the reoxidant of Pd0.