51-35-4

Basic information

• Product Name: trans-4-Hydroxy-L-proline
• Synonyms: H-HYP-OH;H-HYP-OH (TRANS);H-L-HYDROXYPROLINE;H-L-HYP-OH;H-TRANS-HYP-OH;HYDROXYPROLINE;HYDROXY-L-PROLINE;HYDROXY-L-PROLINE, TRANS-4-
• CAS NO: 51-35-4
• Molecular Formula: C₅H₉NO₃
• Molecular Weight: 131.13
• EINECS: 200-091-9
• Product Categories: Nitrogen cyclic compounds;PHARMACEUTICALS;Amino Acids;Pyrrole&Pyrrolidine&Pyrroline;Hydroxyproline [Hyp];Unusual Amino Acids;Biochemistry;Biological-modified Amino Acids;L-Amino Acids;Amino Acids;Amino Acids & Derivatives;Chiral Reagents;Heterocycles
• Mol File: 51-35-4.mol

Chemical Properties

• Melting Point: 273 °C (dec.)(lit.)
• Boiling Point: 242.42°C (rough estimate)
• Flash Point: 168.6 °C
• Appearance: White/Crystals or Crystalline Powder
• Density: 1.3121 (rough estimate)
• Vapor Density: 4.5 (vs air)
• Refractive Index: -75.5 ° (C=4, H2O)
• Storage Temp.: Store at RT.
• Solubility: H2O: 50 mg/mL
• PKA: 1.82, 9.66(at 25℃)
• Water Solubility: 357.8 g/L (20 º C)
• Merck: 14,4840
• BRN: 471933
• CAS DataBase Reference: trans-4-Hydroxy-L-proline(CAS DataBase Reference)
• NIST Chemistry Reference: trans-4-Hydroxy-L-proline(51-35-4)
• EPA Substance Registry System: trans-4-Hydroxy-L-proline(51-35-4)

Safety Data

• Hazard Codes: Xi,Xn
• Statements: 36/37/38-22
• Safety Statements: 24/25-36/37/39-27-26
• WGK Germany: 3
• RTECS: TW3586500
• TSCA: Yes
• HazardClass: IRRITANT
• Hazardous Substances Data: 51-35-4(Hazardous Substances Data)

Usage

Uses

Used in Pharmaceutical Industry:
L-Hydroxyproline is used as a pharmaceutical secondary standard for application in quality control, providing pharma laboratories and manufacturers with a convenient and cost-effective alternative to the preparation of in-house working standards.
Used in Industrial Production:
L-Hydroxyproline is used as a versatile reagent for the synthesis of neuroexcitatory kainoids and antifungal echinocandins. Several microorganisms producing proline trans-4and cis-3-hydroxylase have been discovered, and these enzymes have been applied to the industrial production of trans-4and cis-3-hydroxy-L-proline.
Used in Skincare Industry:
L-Hydroxyproline is used as a skin-conditioning amino acid, as it is a component of collagen, which plays a crucial role in maintaining skin elasticity and structure.
Used in Research and Development:
L-Hydroxyproline is used in research and development for the study of collagen synthesis, as it is a key component in the formation of collagen fibers. This makes it an essential tool for understanding the processes involved in wound healing, tissue repair, and the development of connective tissues.

Production Methods

In the past L-Hydroxyproline was isolated by hydrolysis of animal collagen, e. g. gelatine or collagen, of which it is a major constituent. L-Hydroxyproline is an unnatural amino acid which is made in the body by hydroxylation of L-Proline. The presence of L-Hydroxyproline and proline are key to maintaining the stability of the tight collagen helix. Today L-Hydroxyproline is manufactured by bio-catalysed hydroxylation of proline in bacteria. Together with its other isomers, L-Hydroxyproline is also used as an inter mediate for a range of pharmaceutical active ingredients. Produced by hydroxylation of L-proline after protein synthesis. It is contained rich in collagen and elastin. Known to stabilization of triple-helix structure of collagen. Widely used as an intermediate for medicines.

Biochem/physiol Actions

Trans-4-Hydroxy-L-proline is used in the organic synthesis of depsilairdin analogues, noncompetitive peptidomimetic inhibitors of multidrug resistance P-glycoprotein and 3-guaninyl-5-hydroxymethyl-2-pyrrolidinone (4) or 3-adeninyl-5-hydroxymethyl-2-pyrrolidinone (5) nucleoside analogues.

Purification Methods

Crystallise it from MeOH/EtOH (1:1). Separation from normal allo-isomer can be achieved by crystallisation of the copper salts [see Levine Biochemical Preparations 8 114 1961]. Separation from proline is achieved via the crystalline picrate, CdCl2, or acid ammonium rhodanate salts [see Greenstein & Winitz The Chemistry of the Amino Acids J. Wiley, Vol 3 p 2182 1961, Kapfhammer & Mohn Z Physiol Chem 306 76 1956]. [Beilstein 22/5 V 7.]

InChI:InChI:1S/C5H9NO3/c7-3-1-4(5(8)9)6-2-3/h3-4,6-7H,1-2H2,(H,8,9)

Upstream product

• 217184-95-7 4(R)-hydroxyproline methyl ester 
• 2443-30-3 N-nitrosohydroxyproline 
• 7732-18-5 water 
• 609-36-9 rac-Pro-OH 
• 81102-37-6 5-Formyl-2-(1-phenyl-propyl)-isoxazolidine-3-carboxylic acid methyl ester 
• 77287-34-4 formamide 
• 43176-83-6 (2S,4R)-N-acetyl-4-benzoyloxy-proline 
• 618-28-0 trans-4-hydroxy-D,L-proline 
• 103078-90-6 N-(3,5-dinitrobenzoyl)-(4R)-hydroxy-L-proline 
• 74844-91-0 1-tert-butyl 2-methyl (2S,4R)-4-hydroxy-1,2-pyrrolidinedicarboxylate 
• 13726-69-7 (2S,4R)-4-hydroxy-1-[(2-methylpropan-2-yl)oxycarbonyl]pyrrolidine-2-carboxylic acid 
• 108782-02-1 (2S,4R)-N-Methoxycarbonyl-4-<(tert-butyl)dimethylsilyloxy>pyrrolidin-2-carbonsaeure 
• 97652-00-1 (2R,5S,7R)-2-(tert-butyl)-4-oxo-3-oxa-1-azabicyclo<3.3.0>oct-7-yl acetate 
• 153790-69-3 (2S,4R)-<4-2H1>-proline 

Downstream Products

• 110-80-5 2-ethoxy-ethanol 
• 2443-30-3 N-nitrosohydroxyproline 
• 640-61-9 N-methyl-p-toluenesulfonylamide 
• 1060936-14-2 1-Amino-1-carboxy-2-methyl-propane-2-thiol anion 
• 897046-42-3 1-[(1,1-dimethylethoxy)-carbonyl]-4-hydroxy-2-pyrrolidine carboxylic acid methyl ester 
• 4252-82-8 4-hydroxy-N-methylproline 
• 300409-52-3 (2S,4R)-2-benzyl 1-tert-butyl 4-(benzyloxy)pyrrolidine-1,2-dicarboxylate 
• 40350-82-1 1-(t-butoxycarbonyl)-4-hydroxyproline 
• 217184-95-7 4(R)-hydroxyproline methyl ester 
• 175168-65-7 L-hydroxyproline isopropylate 
• 50424-51-6 (2R,11aS)-2-hydroxy-1,2,3,10,11,11a-hexahydro-5H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11-dione 
• 1330763-18-2 5-tert-butoxycarbonyl-2-oxa-5-azabicyclo[2.2.1]heptane-1-carboxylic acid 
• 876317-19-0 ⁽²⁸⁾-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecarboxylic acid 

Relevant articles and documents

Recharacterization of the mammalian cytosolic type 2 (R)-β-hydroxybutyrate dehydrogenase as 4-oxo-L-proline reductase (EC 1.1.1.104)

Early studies revealed that chicken embryos incubated with a rare analog of L-proline, 4-oxo-L-proline, showed increased levels of the metabolite 4-hydroxy-L-proline. In 1962, 4-oxo-L-proline reductase, an enzyme responsible for the reduction of 4-oxo-L-proline, was partially purified from rabbit kidneys and characterized biochemically. However, only recently was the molecular identity of this enzyme solved. Here, we report the purification from rat kidneys, identification, and biochemical characterization of 4-oxo-L-proline reductase. Following mass spectrometry analysis of the purified protein preparation, the previously annotated mammalian cytosolic type 2 (R)-βhydroxybutyrate dehydrogenase (BDH2) emerged as the only candidate for the reductase. We subsequently expressed rat and human BDH2 in Escherichia coli, then purified it, and showed that it catalyzed the reversible reduction of 4-oxo-L-proline to cis-4-hydroxy-L-proline via chromatographic and tandem mass spectrometry analysis. Specificity studies with an array of compounds carried out on both enzymes showed that 4-oxo-L-proline was the best substrate, and the human enzyme acted with 12,500-fold higher catalytic efficiency on 4-oxo-L-proline than on (R)-β-hydroxybutyrate. In addition, human embryonic kidney 293T (HEK293T) cells efficiently metabolized 4-oxo-L-proline to cis-4-hydroxy-L-proline, whereas HEK293T BDH2 KO cells were incapable of producing cis-4-hydroxy-L-proline. Both WT and KO HEK293T cells also produced trans-4-hydroxy-L-proline in the presence of 4-oxo-L-proline, suggesting that the latter compound might interfere with the trans-4-hydroxy-L-proline breakdown in human cells. We conclude that BDH2 is a mammalian 4-oxo-L-proline reductase that converts 4-oxo-L-proline to cis-4-hydroxy-L-proline and not to trans-4-hydroxy-L-proline, as originally thought. We also hypothesize that this enzyme may be a potential source of cis-4-hydroxy-L-proline in mammalian tissues.

Discovery of New Fe(II)/α-Ketoglutarate-Dependent Dioxygenases for Oxidation of l-Proline

Genome mining for novel Fe(II)/α-ketoglutarate-dependent dioxygenases (αKGDs) to expand the enzymatic repertoire in the oxidation of l-proline is reported. Through clustering of proteins, we predicted regio- and stereoselectivity in the hydroxylation reaction and validated this hypothesis experimentally. Two novel byproducts in the reactions with enzymes from Bacillus cereus and Streptomyces sp. were isolated, and the structures were determined to be a 3,4-epoxide and a 3,4-diol, respectively. The mechanism for the formation of the epoxide was investigated by performing an 18O-labeling experiment. We propose that the mechanism proceeds via initial cis-3-hydroxylation followed by ring closure. A biocatalytic step was run on subgram quantities of starting material without any significant optimization of the conditions. However, the substrate concentration was 40-fold higher than the usual reported titers for recombinant P450-mediated hydroxylations, showing the synthetic potential of αKGDs on a preparative scale.

Studies on the selectivity of proline hydroxylases reveal new substrates including bicycles

Studies on the substrate selectivity of recombinant ferrous-iron- and 2-oxoglutarate-dependent proline hydroxylases (PHs) reveal that they can catalyse the production of dihydroxylated 5-, 6-, and 7-membered ring products, and can accept bicyclic substrates. Ring-substituted substrate analogues (such hydroxylated and fluorinated prolines) are accepted in some cases. The results highlight the considerable, as yet largely untapped, potential for amino acid hydroxylases and other 2OG oxygenases in biocatalysis.

Discovery of new A- and B-type laxaphycins with synergistic anticancer activity

Two new cyclic lipopeptides termed laxaphycins B4 (1) and A2 (2) were discovered from a collection of the marine cyanobacterium Hormothamnion enteromorphoides, along with the known compound laxaphycin A. The planar structures were solved based on a combined interpretation of 1D and 2D NMR data and mass spectral data. The absolute configurations of the subunits were determined by chiral LC-MS analysis of the hydrolysates, advanced Marfey's analysis and 1D and 2D ROESY experiments. Consistent with similar findings on other laxaphycin A- and B-type peptides, laxaphycin B4 (1) showed antiproliferative effects against human colon cancer HCT116 cells with IC50 of 1.7 μM, while laxaphycins A and A2 (2) exhibited weak activities. The two major compounds isolated from the sample, laxaphycins A and B4, were shown to act synergistically to inhibit the growth of HCT116 colorectal cancer cells.

Peptide Tyrosinase Activators

Peptides that increase melanin synthesis are provided. These peptides include pentapeptides YSSWY, YRSRK, and their variants. The peptides may activate the enzymatic activity of tyrosinase to increase melanin synthesis. The pharmaceutical, cosmetic, and other compositions including the peptides are also provided. The methods of increasing melanin production in epidermis of a subject are provided where the methods include administering compositions comprising an amount of one or more peptides effective to increase the melanin production. The methods also include treating vitiligo or other hypopigmentation disorders with compositions including one or more peptides.

Biochemical characterisation and assessment of fibril-forming ability of collagens extracted from Bester sturgeon Huso huso × Acipenser ruthenus

Collagens purified from Bester sturgeon organs were characterised biochemically, and their fibril-forming abilities and fibril morphologies formed in vitro clarified. Yields of collagens were 2.1%, 11.9%, 0.4%, 18.1%, 0.4%, 0.8% and 0.03% (collagen dry weight/tissue wet weight) from scales, skin, muscle, swim bladder, digestive tract, notochord and snout cartilage, respectively. Using SDS-PAGE and amino acid composition analyses, collagens from scales, skin, muscle, the swim bladder and digestive tract were characterised as type I, and collagens from the notochord and snout cartilage as type II. Denaturation temperatures of the collagens, measured using circular dichroism, were 29.6, 26.8, 29.0, 32.9, 31.6 and 36.3 °C in scales, skin, muscle, swim bladder, digestive tract, and notochord, respectively. For fibril formation, swim bladder and skin collagen showed a more rapid rate of increase in turbidity, a shorter time to attain the maximum turbidity, and formed thicker fibrils compared with porcine tendon type I collagen.

Pneumocandin biosynthesis: Involvement of a trans-selective proline hydroxylase

Echinocandins are cyclic nonribosomal hexapeptides based mostly on nonproteinogenic amino acids and displaying strong antifungal activity. Despite previous studies on their biosynthesis by fungi, the origin of three amino acids, trans-4-and trans-3-hydroxyproline, as well as trans-3-hydroxy-4-meth-ylproline, is still unknown. Here we describe the identification, overexpression, and characterization of GloF, the first eukaryot-ic a-ketoglutarate/FeII-dependent proline hydroxylase from the pneumocandin biosynthesis cluster of the fungus Glarea loz-oyensis ATCC 74030. In in vitro transformations with L-proline, GloF generates trans-4- and trans-3-hydroxyproline simultaneously in a ratio of 8:1; the latter reaction was previously unknown for proline hydroxylase catalysis. trans-4-Methyl-L-proline is converted into the corresponding trans-3-hydroxypro-line. All three hydroxyprolines required for the biosynthesis of the echinocandins pneumocandins A0 and B0 in G. lozoyensis are thus provided by GloF. Sequence analyses revealed that GloF is not related to bacterial proline hydroxylases, and none of the putative proteins with high sequence similarity in the databases has been characterized so far.

Substrate specificity and stereoselectivity of two Sulfolobus 2-keto-3-deoxygluconate aldolases towards azido-substituted aldehydes

The 2-keto-3-deoxygluconate aldolases (KDGAs) isolated from Sulfolobus species convert pyruvate and glyceraldehyde reversibly into 2-keto-3-deoxygluconate and -galactonate. As a result of their high thermostability and activity on nonphosphorylated substrates, KDGA enzymes have potential as biocatalysts for the production of building blocks for fine chemical and pharmaceutical applications. Up to now, wild-type enzymes have only shown moderate stereocontrol for their natural reaction. However, if a set of azido-functionalized aldehydes were applied as alternative acceptors in the reaction with pyruvate, the stereoselectivity was strongly increased to give enantiomeric or diastereomeric excess values up to 97 %. The Sulfolobus acidocaldarius KDGA displayed a higher stereoselectivity than Sulfolobus solfataricus KDGA for all tested reactions. The azido-containing products are useful chiral intermediates in the synthesis of nitrogen heterocycles. Taming the wild-type: Two 2-keto-3-deoxygluconate aldolases from Sulfolobus species readily couple azido-substituted aldehydes to pyruvate in a stereoselective manner. The resulting compounds yield chiral nitrogen heterocycles upon reduction.

PROCESS FOR PRODUCING SOLID AMINO ACID

The problem to be solved by the present invention is to ea lily and efficiently produce an amino acid having 2 to 7 carbon atoms as a high-purity solid without complicated operation, which is useful as a synthetic intermediate for medicines or agrochemicals. The present invention is characterized in comprising a step of precipitating solid amino acid with high purity. In the present invention, the by-produced salt composed of the sulfonic acid and the amine was removed to the mother liquor by reacting an amine with a sulfonic acid salt of amino acid in an aprotic polar solvent, or by reacting a sulfonic acid with an amine salt of amino acid in an aprotic polar solvent. The sulfonic acid salt of amino acid, for example, may be produced by reacting a N-(tert-butoxycarbonyl) amino acid with a sulfonic acid, or by reacting an amino acid tert-butyl ester with a sulfonic acid.

Meteorites as catalysts for prebiotic chemistry

From outer space: Twelve meteorite specimens, representative of their major classes, catalyse the synthesis of nucleobases, carboxylic acids, aminoacids and low-molecular-weight compounds from formamide (see figure). Different chemical pathways are identified, the yields are high for a prebiotic process and the products come in rich and composite panels.