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Showing 101 - 150 of 68069 compounds
Compound ID Compound Pathways


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(R)-3-Hydroxydecanoic acid

In humans fatty acids are predominantly formed in the liver and adipose tissue, and mammary glands during lactation.(R)-3-Hydroxydecanoic acid is an intermediate in fatty acid biosynthesis. Specifically,(R)-3-Hydroxydecanoic acid is converted from 3-Oxodecanoic acid via two enzymes; fatty-acid Synthase and 3-oxoacyl- [acyl-carrier- protein] reductase.( EC: and EC:


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(R)-3-Hydroxydodecanoic acid

In humans fatty acids are predominantly formed in the liver and adipose tissue, and mammary glands during lactation.(R)-3-Hydroxydodecanoic acid is an intermediate in fatty acid biosynthesis. Specifically,(R)-3-Hydroxydodecanoic acid is converted from 3-Oxo-Dodecanoic acid via two enzymes; fatty-acid Synthase and 3-oxoacyl-[acyl-carrier-protein] reductase (EC: and EC:


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(R)-3-Hydroxyhexanoic acid

(R)-3-Hydroxyhexanoic acid is fatty acid formed by the action of fatty acid synthases from acetyl-CoA and malonyl-CoA precursors. It is involved in the fatty acid biosynthesis. Specifically, it is the product of reaction between 3-Oxohexanoic acid and 2 enzymes; fatty-acid Synthase and 3-oxoacyl- [acyl-carrier-protein] reductase.


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(R)-3-Hydroxyoctanoic acid

In humans fatty acids are predominantly formed in the liver and adipose tissue, and mammary glands during lactation. (R)-3-Hydroxyoctanoic acid is an intermediate in fatty acid biosynthesis. Specifically, (R)-3-Hydroxyoctanoic acid is converted from 3-Oxo-Octanoic acid via enzymes; fatty-acid Synthase and 3-oxoacyl- [acyl-carrier-protein] reductase. (E.C: and E.C:




The D-enantiomer of citramalic acid (ChEBI ID: 15586).


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(R)-lipoic acid

Lipoic acid is a vitamin-like antioxidant that acts as a free-radical scavenger. Alpha-lipoic acid is also known as thioctic acid. It is a naturally occurring compound that is synthesized by both plants and animals. Lipoic acid contains two thiol groups which may be either oxidized or reduced. The reduced form is known as dihydrolipoic acid (DHLA). Lipoic acid (Delta E= -0.288) is therefore capable of thiol-disulfide exchange, giving it antioxidant activity. Lipoate is a critical cofactor for aerobic metabolism, participating in the transfer of acyl or methylamine groups via the 2-Oxoacid dehydrogenase (2-OADH) or alpha-ketoglutarate dehydrogenase complex. This enzyme catalyzes the conversion of alpha-ketoglutarate to succinyl CoA. This activity results in the catabolism of the branched chain amino acids (leucine, isoleucine and valine). Lipoic acid also participates in the glycine cleavage system(GCV). The glycine cleavage system is a multi-enzyme complex that catalyzes the oxidation of glycine to form 5,10 methylene tetrahydrofolate, an important cofactor in nucleic acid synthesis. Since Lipoic acid is an essential cofactor for many enzyme complexes, it is essential for aerobic life as we know it. This system is used by many organisms and plays a crucial role in the photosynthetic carbon cycle. Lipoic acid was first postulated to be an effective antioxidant when it was found it prevented vitamin C and vitamin E deficiency. It is able to scavenge reactive oxygen species and reduce other metabolites, such as glutathione or vitamins, maintaining a healthy cellular redox state. Lipoic acid has been shown in cell culture experiments to increase cellular uptake of glucose by recruiting the glucose transporter GLUT4 to the cell membrane, suggesting its use in diabetes. Studies of rat aging have suggested that the use of L-carnitine and lipoic acid results in improved memory performance and delayed structural mitochondrial decay. As a result, it may be helpful for people with Alzheimer's disease or Parkinson's disease. -- Wikipedia.












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(S)-2,3,4,5-Tetrahydropiperidine-2-carboxylate is a cyclic intermediate in lysine degradation. L-Lysine is an essential amino acid that is a necessary building block for all protein in the body and It plays a major role in calcium absorption; building muscle protein; recovering from surgery or sports injuries; and the body's production of hormones, enzymes, and antibodies. In lysine degradation pathway, (S)-2,3,4,5-Tetrahydropiperidine-2-carboxylate is a substrate for L-aminoadipate-semialdehyde dehydrogenase (amaA) and can be formed by spontaneous cyclization of 2-aminoadipate-6-semialdehyde.


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(S)-2,3-Epoxysqualene is an intermediate in the biosynthesis of Terpenoid. It is a substrate for Squalene monooxygenase and Lanosterol synthase.


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(S)-2-Aceto-2-hydroxybutanoic acid

(S)-2-Aceto-2-hydroxybutanoic acid is an intermediate in branched chain amino acid metabolism. It is converted from 2-oxobutanoate or 2-hydoxyethyl ThPP via acetolactate synthase.


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(S)-2-Acetolactate is an intermediate in the biosynthesis of valine, leucine and isoleucine (KEGG ID C06010 ). It is the sixth to last step in the synthesis of protein and is converted from 2-hydroxy-3-methyl-2-oxobutanoate via the enzyme acetolactate synthase [EC:]. It is then converted to 3-hydroxy-3-methyl-2-oxobutanoate via the enzyme ketol-acid reductoisomerase [EC:].


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(s)-2-amino-6-oxohexanoate is part of the Amino-acid degradation, Lysine degradation, Amine and polyamine biosynthesis, Glycolysis / Gluconeogenesis, Ascorbate and aldarate metabolism, Fatty acid metabolism, Glycine, serine and threonine metabolism, Valine, leucine and isoleucine degradation, Lysine biosynthesis, Arginine and proline metabolism, Histidine metabolism, Tryptophan metabolism, beta-Alanine metabolism, Glycerolipid metabolism, Pyruvate metabolism, and Propanoate metabolism pathways. It is a substrate for: Alpha-aminoadipic semialdehyde synthase, mitochondrial, Alpha-aminoadipic semialdehyde dehydrogenase, and 5-phosphohydroxy-L-lysine phospho-lyase.


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(S)-2-Methyl-1-butanol is found in fruits. (S)-2-Methyl-1-butanol is isolated from grapes, apples, tomatoes etc. (S)-2-Methyl-1-butanol belongs to the family of Primary Alcohols. These are compounds comprising the primary alcohol functional group, with the general strucuture RCOH (R=alkyl, aryl).


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(S)-3-Hydroxydodecanoyl-CoA is a human metabolite involved in the fatty acid elongation in mitochondria pathway. The enzyme long-chain-3-hydroxyacyl-CoA dehydrogenase catalyzes the conversion of 3-Oxododecanoyl-CoA to (S)-3-Hydroxydodecanoyl-CoA.


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(S)-3-Hydroxyhexadecanoyl-CoA is a beta-oxidation intermediate derivative of palmitoyl-CoA and the substrate of the enzyme peroxisomal acyl-CoA thioesterase 2 (PTE-2, EC, which is localized in the peroxisome. The peroxisomal beta-oxidation system contains two sets of enzymes, one of which is involved in the oxidation of branched chain fatty acids and intermediates in the hepatic bile acid biosynthetic pathway and consists of one or two branched-chain acyl-CoA oxidase(s), a D-specific bifunctional protein and the sterol carrier-like protein x (SCPx). Peroxisomes are cellular organelles present in all eukaryotic cells. They play an indispensable role in the metabolism of a variety of lipids including very long-chain fatty acids, dicarboxylic fatty acids, bile acids, prostaglandins, leukotrienes, thromboxanes, pristanic acid, and xenobiotic fatty acids. (S)-3-Hydroxyhexadecanoyl-CoA may accumulate intracellularly in certain long-chain fatty acid/j-oxidation deficiencies. Succinate-driven synthesis of ATP from ADP and phosphate is progressively inhibited by increasing concentrations of (S)-3-Hydroxyhexadecanoyl-CoA. (PMID: 11673457, 8739955, 7662716).


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(S)-3-Hydroxyisobutyric acid

(S)-3-Hydroxyisobutyric (3-HIBA) acid is an organic acid. 3-HIBA is an intermediate in L-valine metabolism. 3-HIBA plays an important role in the diagnosis of the very rare inherited metabolic diseases 3-hydroxyisobutyric aciduria (OMIM 236795) and methylmalonic semialdehyde dehydrogenase deficiency (OMIM 603178). Patients with 3-hydroxyisobutyric aciduria excrete a significant amount of 3-HIBA not only during the acute stage but also when stable. 3-hydroxyisobutyric aciduria is caused by a 3-hydroxyisobutyryl-CoA dehydrogenase deficiency (PMID: 18329219). The severity of this disease varies from case to case. Most patients exhibit dysmorphic features, such as a small triangular face, a long philtrum, low set ears and micrognathia (PMID: 113770040, 10686279). Lactic acidemia is also found in the affected patients, indicating that mitochondrial dysfunction is involved. 3-hydroxyisobutyrate appears to specifically inhibit the function of the respiratory chain complex I-III and mitochondrial creatine kinase (PMID: 18329219).


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(S)-3-Hydroxyisobutyryl-CoA is s metabolite of 3-hydroxyisobutyryl-CoA hydrolase (EC ) during beta-alanine metabolism (KEGG 00410), propanoate metabolism (KEGG 00640), and valine, leucine and isoleucine degradation (KEGG 00280). Deficiencies of this enzyme in valine degradation can result in hypotonia, poor feeding, motor delay, and subsequent neurological regression in infancy, episodes of ketoacidosis and Leigh-like changes in the basal ganglia on a magnetic resonance imaging scan (PMID 17160907).





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(S)-3-Hydroxytetradecanoyl-CoA is an intermediate in Fatty acid elongation in mitochondria. (S)-3-Hydroxytetradecanoyl-CoA is the 7th to last step in the synthesis of Hexadecanoic acid and is converted from 3-Oxotetradecanoyl-CoA via the enzyme long-chain 3-hydroxyacyl-CoA dehydrogenase (EC It is then converted to trans-Tetradec-2-enoyl-CoA via the enzyme enoyl-CoA hydratase (EC









(S)-4-Hydroxy-5-(3,4,5-trihydroxyphenyl)valeric acid


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(S)-5-Diphosphomevalonic acid

5-pyrophosphomevalonate is a metabolic intermediate in the mevalonate pathway, catalyzed by the enzyme phosphomevalonate kinase from 5-phosphomevalonate. (wikipedia).


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(S)-Abscisic acid

(S)-Abscisic acid is found in alcoholic beverages. (S)-Abscisic acid is a constituent of cabbage, potato, lemon etc. (S)-Abscisic acid belongs to the family of Monocyclic Monoterpenes. These are monoterpenes containing 1 ring in the isoprene chain.


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(S)-alpha-Terpineol is found in cinnamon. Terpineol is a naturally occurring monoterpene alcohol that has been isolated from a variety of sources such as cajuput oil, pine oil, and petitgrain oil. There are three isomers, alpha-, beta-, and gamma-terpineol, the last two differing only by the location of the double bond. Terpineol is usually a mixture of these isomers with alpha-terpineol as the major constituent. (Wikipedia) (S)-alpha-Terpineol belongs to the family of Monoterpenes. These are compounds contaning a chain of two isoprene units.


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(S)-b-aminoisobutyric acid

Beta-Aminoisobutyric acid is a non-protein amino acid originating from the catabolism of thymine and valine. The concentration of beta-Aminoisobutyric acid is normally low in urine as beta-Aminoisobutyric acid is further catabolized by b-aminoisobutyrate aminotransferases to methylmalonic acid semialdehyde and propionyl-CoA. beta-Aminoisobutyric acid occurs in two isomeric forms and both enantiomers of beta-Aminoisobutyric acid can be detected in human urine and plasma. In plasma, the S-enantiomer is the predominant type due to active renal reabsorption. In contrast, urine almost exclusively contains the R-enantiomer of beta-Aminoisobutyric acid, which is eliminated both by filtration and tubular secretion. Persistently increased levels of beta-Aminoisobutyric acid have been observed in individuals with a deficiency of R (-) -b-aminoisobutyrate-pyruvate aminotransferase. In addition, transient high levels of beta-Aminoisobutyric acid have been observed under a variety of pathological conditions such as lead poisoning, starvation, in total body irradiation and in a number of malignancies. The S-enantiomer of beta-Aminoisobutyric acid is predominantly derived from the catabolism of valine. It has been suggested that an altered homoeostasis of b-alanine underlies some of the clinical abnormalities encountered in patients with a dihydropyrimidine dehydrogenase (DPD) deficiency. DPD constitutes the first step of the pyrimidine degradation pathway, in which the pyrimidine bases uracil and thymine are catabolized to b-alanine and the R-enantiomer of beta-Aminoisobutyric acid respectively. In normal individuals with an intact pyrimidine degradation pathway, R-methylmalonic acid semialdehyde can be synthesized directly from the catabolism of thymine. Hence, there might be less cross-over between the valine and thymine pathway, allowing the conversion of S-methylmalonic acid semialdehyde into S-beta-Aminoisobutyric acid and the subsequent accumulation of S-beta-Aminoisobutyric acid in plasma. (PMID: 14705962, 14292857, 14453202).


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(S)-Hydroxydecanoyl-CoA has a role in the synthesis and oxidation of fatty acids. It is involved in fatty acid elongation in mitochondria. In this pathway 3-Oxodecanoyl-CoA is acted upon by two enzymes, 3-hydroxyacyl-CoA dehydrogenase and long-chain-3-hydroxyacyl-CoA dehydrogenase to produce (S)-Hydroxydecanoyl-CoA. Since coenzyme A is chemically a thiol, it can react with carboxylic acids to form thioesters, thus functioning as an acyl group carrier. It assists in transferring fatty acids from the cytoplasm to mitochondria. A molecule of coenzyme A carrying an acetyl group is also referred to as acetyl-CoA. When it is not attached to an acyl group it is usually referred to as CoASH or HSCoA.


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(S)-Hydroxyhexanoyl-CoA is an intermediate in fatty acid metabolism, being the substrate of the enzymes beta-hydroxyacyl-CoA dehydrogenase (EC and 3-hydroxyacyl-CoA dehydrogenase (EC (S)-Hydroxyhexanoyl-CoA is also an intermediate in fatty acid elongation in mitochondria, the substrate of the enzymes enoyl-CoA hydratase (EC and long-chain-enoyl-CoA hydratase (EC (KEGG).


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(S)-Hydroxyoctadecanoyl-CoA is an intermediate of beta-oxidation.


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Coenzyme A is notable for its role in the synthesis and oxidation of fatty acids. Since coenzyme A is chemically a thiol, it can react with carboxylic acids to form thioesters, thus functioning as an acyl group carrier. It assists in transferring fatty acids from the cytoplasm to mitochondria. Specifically (S)-Hydroxyoctanoyl-CoA is involved in fatty acid metabolism. It is the product of a reaction between 3-Oxooctanoyl-CoA and two enzymes; 3-hydroxyacyl-CoA Dehydrogenase and long-chain- 3-hydroxyacyl-CoA dehydrogenase.






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(S)-Methylmalonic acid semialdehyde

Methylmalonic semialdehyde is a metabolite in valine catabolism, inositol metabolism and propanoate metabolism. Methylmalonate-semialdehyde dehydrogenase (MMSDH) catalyses the NAD+ and coenzyme A-dependent conversion of methylmalonate semialdehyde to propionyl-CoA in the distal region of the L-valine catabolic pathway. MMSDH is located within the mitochondria; direct enzymatic assay of MMSDH is difficult since the substrate, methylmalonate semialdehyde, is both commercially unavailable and notoriously unstable as a b-keto acid. (PMID: 10947204).




CC(CO)O1,2-Propanediol (1,2-PDO) occurs in two stereoisomers - (S)-propane-1,2-diol and (R)-propane-1,2-diol. Both forms are produced by certain organisms. For example, during the catabolism of 6-deoxyhexoses [Suzuki68, Weimer84] or during the fermentation of glucose via methylglyoxal [TranDin85, Cameron86]. 1,2-PDO is a bulk industrial chemical with a global demand of around 1.36 million tons/year [Shelley07]. It is widely used in the production of unsaturated polyester resin and as a nontoxic replacement of ethylene glycol in deicer and antifreeze products. Current commercial production of 1,2-PDO is mainly by a synthetic process that results in a racemic mixture.


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(S)-Succinyldihydrolipoamide is a metabolite (a product as well as a substrate) in glutamate degradation.


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(S)-Ureidoglycolic acid

(S)-Ureidoglycolic acid is a substrate of enzyme ureidoglycolate dehydrogenase [EC] in purine metabolism pathway (KEGG).







A farnesene synthesized in farnesene biosynthesis.


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1,2-Diacyl-sn-glycerol (didodecanoyl, n-C12:0)


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At physiological pH, this molecule, 1,2-dihydroxy-3-keto-5-methylthiopentene, is a monoanion, 1,2-dihydroxy-3-keto-5-methylthiopentene anion. 1,2-dihydroxy-3-keto-5-methylthiopentene anion, an aci-reductone, is believed to be an unstable intermediate in the methionine salvage pathway in Klebsiella pneumoniae. (MetaCyc).


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1,3,7-Trimethyluric acid

1,3,7-Trimethyluric acid is a methyl derivative of uric acid, found occasionally in human urine. 1,3,7-Trimethyluracil is one of the purine components in urinary calculi. Methylated purines originate from the metabolism of methylxanthines (caffeine, theophylline and theobromine). Methyluric acids are indistinguishable from uric acid by simple methods routinely used in clinical laboratories, requiring the use of high-performance liquid chromatography (HPLC). Purine derivatives in urinary calculi could be considered markers of abnormal purine metabolism. The content of a purine derivative in stone depends on its average urinary excretion in the general population, similarity to the chemical structure of uric acid, and content of the latter in stone. This suggests that purines in stones represent a solid solution with uric acid as solvent. It is also plausible that methylxanthines, ubiquitous components of the diet and drugs, are involved in the pathogenesis of urolithiasis. Caffeine is metabolized via successive pathways mainly catalyzed by CYP1A2, xanthine oxidase or N-acetyltransferase-2 to give 14 different metabolites. CYP1A2 activity shows an inter-individual variability among the population. CYP1A2, an isoform of the CYP1A cytochrome P450 super-family, is involved in the metabolism of many drugs and plays a potentially important role in the induction of chemical carcinogenesis. (PMID: 11712316, 15833286, 3506820, 15013152).




A β-D-glucan in which the glucose units are connected by (1→3) linkages.


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1,3-Diaminopropane is a stable, flammable and highly hydroscopic fluid. It is a polyamine that is normally quite toxic if swallowed, inhaled or absorbed through the skin. It is a catabolic byproduct of spermidine. It is also a precursor in the enzymatic synthesis of beta-alanine. 1, 3-Diaminopropane is involved in the arginine/proline metabolic pathways and the beta-alanine metabolic pathway.


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Mannan is a polymer of mannose, linked by 1->4 beta linkages. It is an intermediate in Fructose and mannose metabolism (KEGG:C00464). It is generated from GDP-D-mannose via the enzyme transferases [EC 2.4.1.-] and is then converted to D-mannose via the enzyme mannan 1,2-(1,3)-alpha-mannosidase [EC]. 1,4-beta-D-Mannan is involved in the fructose and mannose metabolism system. 1,4-beta-D-Mannan is produced from GDP-D-mannose by the action of [E2.4.1.-]. 1,4-beta-D-Mannan is converted to D-mannose by mannan endo-1,4-beta-mannosidase [EC:]. An example structure is given, and Mannan is a polymer that can contain more than 10 individual sugars.








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Dithiothreitol (DTT) is the common name for a small-molecule redox reagent known as Cleland's reagent. DTT's formula is C4H10O2S2 and the molecular structure of its reduced form is shown at the right; its oxidized form is a disulfide-bonded 6-membered ring (shown below). Its name derives from the four-carbon sugar, threose. DTT has an epimeric ('sister') compound, dithioerythritol. A common use of DTT is as a reducing or "deprotecting" agent for thiolated DNA. The terminal sulfur atoms of thiolated DNA have a tendency to form dimers in solution, especially in the presence of oxygen. Dimerization greatly lowers the efficiency of subsequent coupling reactions such as DNA immobilization on gold in biosensors. Typically DTT is mixed with a DNA solution and allowed to react, and then is removed by filtration (for the solid catalyst) or by chromatography (for the liquid form). The DTT removal procedure is often called "desalting.". DTT is frequently used to reduce the disulfide bonds of proteins and, more generally, to prevent intramolecular and intermolecular disulfide bonds from forming between cysteine residues of proteins. However, even DTT cannot reduce buried (solvent-inaccessible) disulfide bonds, so reduction of disulfide bonds is sometimes carried out under denaturing conditions (e.g., at high temperatures, or in the presence of a strong denaturant such as 6 M guanidinium hydrochloride, 8 M urea, or 1% sodium dodecylsulfate). Conversely, the solvent exposure of different disulfide bonds can be assayed by their rate of reduction in the presence of DTT. DTT can also be used as an oxidizing agent. Its principal advantage is that effectively no mixed-disulfide species are populated, in contrast to other agents such as glutathione. In very rare cases, a DTT adduct may be formed, i.e., the two sulfur atoms of DTT may form disulfide bonds to different sulfur atoms; in such cases, DTT cannot cyclize since it has no remaining free thiols. Due to air oxidation, DTT is a relatively unstable compound whose useful life can be extended by refrigeration and handling in an inert atmosphere. Since protonated sulfurs have lowered nucleophilicities, DTT becomes less potent as the pH lowers. Tris(2-carboxyethyl)phosphine HCl (TCEP hydrochloride) is an alternative which is more stable and works even at low pH.




Showing 101 - 150 of 68069 compounds