- Structure-activity relationship studies of dipeptide-based hepsin inhibitors with Arg bioisosteres
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Hepsin is a type II transmembrane serine protease (TTSP) associated with cell proliferation and overexpressed in several types of cancer including prostate cancer (PCa). Because of its significant role in cancer progression and metastasis, hepsin is an attractive protein as a potential therapeutic and diagnostic biomarker for PCa. Based on the reported Leu-Arg dipeptide-based hepsin inhibitors, we performed structural modification and determined in vitro hepsin- and matriptase-inhibitory activities. Comprehensive structure-activity relationship studies identified that the p-guanidinophenylalanine-based dipeptide analog 22a exhibited a strong hepsin-inhibitory activity (Ki = 50.5 nM) and 22-fold hepsin selectivity over matriptase. Compound 22a could be a prototype molecule for structural optimization of dipeptide-based hepsin inhibitors.
- Kwon, Hongmok,Ha, Hyunsoo,Jeon, Hayoung,Jang, Jaebong,Son, Sang-Hyun,Lee, Kiho,Park, Song-Kyu,Byun, Youngjoo
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supporting information
(2020/12/25)
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- Synthesis of task-specific imidazolium ionic liquid as an efficient catalyst in acetylation of alcohols, phenols, and amines
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Herein, we report the synthesis of task-specific amino-functionalized imidazolium ionic liquid, acetate1-(2-tert-butoxycarbonylamino-ethyl)-3-methyl-3H-imidazol-1-ium; (Boc-NH-EMIM.OAc), as an efficient catalyst for the acetylation of alcohols, phenols, and amines in the presence of acetic anhydride (acetylating reagent). Remarkably, acetic anhydride in the presence of 10?molpercent of catalyst (Boc-NH-EMIM.OAc) under solvent-free conditions showed excellent acetylation activity in shorter duration of time. On the basis of this, a general procedure for acetylation of alcohols, phenols, and amines has been developed. The ionic liquid (Boc-NH-EMIM.OAc) can be readily recovered and reused successfully up to four consecutive cycles without any significant loss of its catalytic activity. We have been able to show that this acetylating method has many advantages. It gives high yields, takes shorter time, and develops the possibility of benign environmental-friendly process.
- Chaubey, Snehkrishn A.,Mishra, Roli
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p. 3259 - 3268
(2020/04/17)
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- Bio- And Medicinally Compatible α-Amino-Acid Modification via Merging Photoredox and N-Heterocyclic Carbene Catalysis
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An N-heterocyclic carbene and photoredox cocatalyzed α-amino-acid decarboxylative carbonylation reaction is presented. This method displays good scope generality, providing a direct pathway to access various downstream α-amino ketones under bio- and medicinally compatible conditions. Moreover, this strategy is appealing to chemical biology because it has great potential for the chemical modification of peptides or the late-stage synthesis of keto-peptides.
- Chen, Lei,Du, Ding,Feng, Jie,Gao, Jian,Lu, Tao,Ma, Rui,Shi, Zhihao,Zhang, Kuili
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supporting information
(2020/09/02)
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- GRANZYME B DIRECTED IMAGING AND THERAPY
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Provided herein are heterocyclic compounds useful for imaging Granzyme B. Methods of imaging Granzyme B, combination therapies, and kits comprising the Granzyme B imaging agents are also provided.
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Page/Page column 108
(2019/09/04)
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- Oxidative functionalization of aliphatic and aromatic amino acid derivatives with H2O2 catalyzed by a nonheme imine based iron complex
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The oxidation of a series of N-acetyl amino acid methyl esters with H2O2 catalyzed by a very simple iminopyridine iron(ii) complex 1 easily obtainable in situ by self-assembly of 2-picolylaldehyde, 2-picolylamine, and Fe(OTf)2 was investigated. Oxidation of protected aliphatic amino acids occurs at the α-C-H bond exclusively (N-AcAlaOMe) or in competition with the side-chain functionalization (N-AcValOMe and N-AcLeuOMe). N-AcProOMe is smoothly and cleanly oxidized with high regioselectivity affording exclusively C-5 oxidation products. Remarkably, complex 1 is also able to catalyze the oxidation of the aromatic N-AcPheOMe. A marked preference for the aromatic ring hydroxylation over Cα-H and benzylic C-H oxidation was observed, leading to the clean formation of tyrosine and its phenolic isomers.
- Ticconi, Barbara,Colcerasa, Arianna,Di Stefano, Stefano,Lanzalunga, Osvaldo,Lapi, Andrea,Mazzonna, Marco,Olivo, Giorgio
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p. 19144 - 19151
(2018/05/31)
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- Reactivity of α-Amino Acids in the Reaction with Esters in Aqueous–1,4-Dioxane Media
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The kinetics of the reaction of a series of α-amino acids with 4-nitrophenyl acetate, 4-nitrophenyl benzoate, and 2,4,6-trinitrophenyl benzoate in aqueous 1,4-dioxane medium has been studied. Kinetics of the reactions involving 4-nitrophenyl acetate and 2,4,6-trinitrophenyl benzoate has complied with the Br?nsted dependence and revealed linear correlation between rate constant logarithm and the energy difference of the frontier orbitals of α-amino acids anions.
- Kochetova,Kustova,Kuritsyn
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- Rapid Room-Temperature Gelation of Crude Oils by a Wetted Powder Gelator
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Phase-selective organogelators (PSOGs) not only exhibit ability to phase-selectively congeal oil from oily water but also allow easy separation of gelled oil from the body of water. However, all hitherto reported PSOGs either necessitate carrier solvents for their dissolution or suffer from an extremely slow action in gelling oil in the powder form. A previously unexplored generally applicable wetting strategy is now described to dramatically enhance, by up to two orders of magnitude, gelling speed of the resultant wet but non-sticky gelator in the powder form in crude oils of widely ranging viscosities. Such unprecedented rapid gelling speeds enable rapid gelation of six types of (un)weathered crude oils within minutes at room temperature, making PSOGs one step closer to their eventual practical uses as one of important oil spill control technologies.
- Ren, Changliang,Shen, Jie,Chen, Feng,Zeng, Huaqiang
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supporting information
p. 3847 - 3851
(2017/03/27)
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- Peptide Tyrosinase Activators
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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.
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- PEPTIDOMIMETIC COMPOUNDS AND ANTIBODY-DRUG CONJUGATES THEREOF
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This invention relates to peptidomimetic linkers and anti-body drug conjugates thereof, to pharmaceutical compositions containing them, and to their use in therapy for the prevention or treatment of cancer.
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Page/Page column 138
(2015/07/07)
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- Enantiospecific C-H Activation Using Ruthenium Nanocatalysts
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The activation of C-H bonds has revolutionized modern synthetic chemistry. However, no general strategy for enantiospecific C-H activation has been developed to date. We herein report an enantiospecific C-H activation reaction followed by deuterium incorporation at stereogenic centers. Mechanistic studies suggest that the selectivity for the α-position of the directing heteroatom results from a four-membered dimetallacycle as the key intermediate. This work paves the way to novel molecular chemistry on nanoparticles.
- Taglang, Céline,Martínez-Prieto, Luis Miguel,Del Rosal, Iker,Maron, Laurent,Poteau, Romuald,Philippot, Karine,Chaudret, Bruno,Perato, Serge,Sam Lone, Ana?s,Puente, Céline,Dugave, Christophe,Rousseau, Bernard,Pieters, Grégory
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supporting information
p. 10474 - 10477
(2015/09/02)
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- "Cofactor"-controlled enantioselective catalysis
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We report an achiral bisphosphine rhodium complex equipped with a binding site for the recognition of chiral anion guests. Upon binding small chiral guests-cofactors-the rhodium complex becomes chiral and can thus be used for asymmetric catalysis. Screening of a library of cofactors revealed that the best cofactors lead to hydrogenation catalysts that form the products with high enantioselectivity (ee?s up to 99%). Interestingly, a competition experiment shows that even in a mixture of 12 cofactors high ee is obtained, indicating that the complex based on the best cofactor dominates the catalysis.
- Dydio, Pawel,Rubay, Christophe,Gadzikwa, Tendai,Lutz, Martin,Reek, Joost N. H.
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supporting information; experimental part
p. 17176 - 17179
(2011/12/13)
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- Microwave-assisted synthesis of amide under solvent-free conditions
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An efficient and environmentally friendly synthetic method for the synthesis of primary amides under microwave irradiation was described, in which the primary amine was directly reacted with acid without any catalytic agents. The reaction took place in 8-12-min, which was much shorter than the traditional synthetic methods, with almost quantitative yields. The influential factor of the reaction was discussed. The tautomerization between the carboxylic acid group and the H atom in α-carbon of L-amino acid was observed, presumably a dehydrated intermediate forming from this tautomerized isomer. Copyright Taylor & Francis Group, LLC.
- Wang, Xiao-Jian,Yang, Qian,Liu, Fei,You, Qi-Dong
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p. 1028 - 1035
(2008/09/18)
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- Amidoearbonylation of aldehydes utilizing cobalt oxide-supported gold nanoparticles as a heterogeneous catalyst
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Cobalt oxide-supported gold-nanoparticles-catalyzed transformation of aldehydes and their equivalents to N-acyl-α-arnino acids was achieved. The desired products were obtained in moderate to excellent yields under milder reaction conditions than previous reports employing octacarbonyldicobalt as a catalyst. Copyright
- Hamasaki, Akiyuki,Liu, Xiaohao,Tokunaga, Makoto
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supporting information; experimental part
p. 1292 - 1293
(2009/12/03)
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- Novel phosphine ligands
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The invention is concerned with new phosphine ligands of the formula I wherein R1 and R2 are independently of each other alkyl, aryl, cycloalkyl or heteroaryl, said alkyl, aryl, cycloalkyl or heteroaryl may be substituted by alkyl, alkoxy, halogen, hydroxy, amino, mono- or dialkylamino, aryl, —SO2—R7, —SO3?, —CO—NR8R8′, carboxy, alkoxycarbonyl, trialkylsilyl, diarylalkylsilyl, dialkylarylsilyl or triarylsilyl; R3 is alkyl, cycloalkyl, aryl or heteroaryl; R4′ and R4 signify independently of each other hydrogen, alkyl or optionally substituted aryl; or R4′ and R4 together with the C-atom they are attached to form a 3-8-membered carbocyclic ring; dotted line is absent or is present and forms a double bond; R5 and R6 are independently of each other hydrogen, alkyl or aryl; or linked together to form a 3-8-membered carbocyclic ring or an aromatic ring; R7 is alkyl, aryl or NR8R8′; and R8 and R8′ are independently of each other hydrogen, alkyl or aryl; metal complexes with such ligands as well as the use of such metal complexes as catalysts in asymmetric reactions.
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Page/Page column 24-25
(2010/11/27)
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- METHOD OF AMIDOCARBONYLATION REACTION
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A novel method of an amidocarbonylation reaction among an aldehyde compound, an amide compound, and carbon monoxide, which comprises using a palladium-supporting crosslinked-polymer composition containing palladium clusters having a major-axis length of 20 nm or shorter to conduct the amidocarbonylation reaction. Thus, an N-acyl-±-amino acid can be more efficiently and selectively synthesized in a clean reaction system. Also provided is a catalyst for use in the method.
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Page/Page column 11
(2008/06/13)
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- Palladium-catalyzed amidocarbonylation improved by recyclable ionic liquids
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Two types of ionic liquids (halide anion ionic liquids and Brensted acidic ionic liquids) were first applied to improve the palladium-catalyzed amidocarbonylation. Both the palladium catalyst and the ionic liquids could be recycled at least five times without significant loss in catalytic activity. Georg Thieme Verlag Stuttgart.
- Zhu, Bingchun,Jiang, Xuanzhen
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p. 2795 - 2798
(2008/02/11)
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- A study of amidocarbonylation reactions catalyzed by Pd/HZSM-5
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A HZSM-5-supported palladium catalyst, which was prepared by the conventional impregnation method, was utilized in amidocarbonylation reactions. Several important parameters were optimized to give moderate to excellent yields. The catalyst recycling of Pd/HZSM-5, for the first time, was achieved for at least four run times without depreciation of catalytic activity. The studies of TEM images revealed that agglomeration of the palladium species of Pd/ HZSM-5 catalyst was avoided after reaction, which was quite different from the case of Pd/C catalyst.
- Ke, Wu Yang,Xuan, Zhen Jiang
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p. 806 - 809
(2007/10/03)
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- RESOLUTION OF 3-AMINO ALKYLNITRILES
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The present invention relates to chiral N-acetyl-alpha-amino acid salts of optically active β-amino alkylnitriles, and also to a process for preparing optically active β-amino alkylnitriles by resolving racemic β-amino alkylnitriles using chiral N-acetyl-alpha-amino acids as resolving agent.
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Page/Page column 9
(2008/06/13)
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- D-aminoacylase mutants
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The present invention provides mutant D-aminoacylases and use thereof. The mutant D-aminoacylases are hard to be inhibited by the substrate and, comprise the amino acid sequences of the D-aminoacylase derived from Alcaligenes denitrificans subsp. xylosoxydans MI-4 strain, wherein amino acid residues at specific sites have been modified. The mutants of the present invention have high reaction specificity as well as resistance to inhibition by the substrate. The present invention enables high-yield production of D-amino acids using higher concentrations of N-acyl-DL-amino acid as the substrate. The mutants of the present invention are useful in producing D-tryptophan in particular.
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- Asymmetric catalysis based on chiral phospholanes and hydroxyl phospholanes
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Chiral phosphine ligands derived from chiral natural products including D-mannitol and tartaric acid. The ligands contain one or more 5-membered phospholane rings with multiple chiral centers, and provide high stereoselectivity in asymmetric reactions.
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Page column 26
(2010/02/06)
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- Efficient synthesis of N-acyl-α-amino acids via polymer incarcerated palladium-catalyzed amidocarbonylation
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A novel polymer incarcerated Pd catalyst (PI Pd 7c) was synthesized from amide-containing polymer 6b, and this catalyst was shown to be effective in amidocarbonylation, which is a versatile one-pot method for the preparation of N-acyl-α-amino acids. The reactions proceeded smoothly with a wide variety of substrates, and no leaching of the Pd metal to the reaction mixture was detected.
- Akiyama, Ryo,Sagae, Takahiro,Sugiura, Masaharu,Kobayashi, Shu
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p. 3806 - 3809
(2007/10/03)
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- Employing the structural diversity of nature: Development of modular dipeptide-analogue ligands for ruthenium-catalyzed enantioselective transfer hydrogenation of ketones
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A library of novel dipeptideanalogue ligands based on the combination of tert-butoxycarbonyl(N-Boc)-protected a-amino acids and chiral vicinal amino alcohols were prepared. These highly modular ligands were combined with [{RuCl2(p-cymene)}2 and the resulting metal complexes were screened as catalysts for the enantioselective reduction of acetophenone under transfer hydrogenation conditions using 2-propanol as the hydrogen donor. Excellent enantioselectivity of 1-phenylethanol (up to 98% ee) was achieved with several of the novel catalysts. Although most of the ligands contained two stereocenters, it was demonstrated that the absolute configuration of the product alcohol was determined by the configuration of the amino acid part of the ligand. Employing ligands based on L-amino acids generated S-configured products, and catalysts based on Damino acids favored the formation of the R-configured alcohol. The combination N-Boc-L-alanine and (R)-phenylglycinol (Boc-L-Ab) or its enantiomer (N-Boc-D-alanine and (S)-phenylglycinol, Boc-D-Aa) proved to be the best ligands for the reduction process. Transfer hydrogenation of a number of aryl alkyl ketones were evaluated and excellent enantioselectivity, up to 96 % ee, was obtained.
- Pastor, Isidro M.,Vaestilae, Patrik,Adolfsson, Hans
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p. 4031 - 4045
(2007/10/03)
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- Platinum-catalyzed amidocarbonylation
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The first example of platinum-catalyzed amidocarbonylation of aldehydes with amides and carbon monoxide is described. In contrast to precedent palladium catalysis, a remarkable ligand acceleration by phosphines was observed. Furthermore, an optically active N-acetyl amino acid was partially epimerized under the platinum-catalyzed conditions, while faster racemization was observed under the palladium catalysis.
- Sagae, Takahiro,Sugiura, Masaharu,Hagio, Hiroyuki,Kobayashi, Shu
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p. 160 - 161
(2007/10/03)
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- Heat-stable D-aminoacylase
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The present invention provides a novel D-aminoacylase, as well as method for producing a D-amino acid using the same. In order to achieve the above objective, the present inventors have succeeded in purifying heat-stable D-aminoacylase from microorganisms belonging to the genus Streptomyces by combining various purification methods. Furthermore, the present inventors found that the purified heat-stable D-aminoacylase is useful in industrial production of D-amino acids. By utilizing the heat-stable D-aminoacylase, it is possible to readily and efficiently produce the corresponding D-amino acids from N-acetyl-DL-amino acids (for example, N-acetyl-DL-methionine, N-acetyl-DL-valine, N-acetyl-DL-tryptophan, N-acetyl-DL-phenylalanine, N-acetyl-DL-alanine, N-acetyl-DL-leucine, and so on).
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- Insight into β-hairpin stability: A structural and thermodynamic study of diastereomeric β-hairpin mimeticsy
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Two diastereomers of a model β-hairpin peptide mimetic were synthesized and studied with a combination of experimental (NMR, X-ray, CD, MS, IR) and computational methods (Monte Carlo/molecular mechanics calculations). The secondary structure-stabilizing effects of hydrophobic interactions and hydrogen bonding were investigated. Comparison of the extent of folded hairpin population in non-competitive, polar aprotic, and polar protic solvents illustrates the critical role of intramolecular hydrogen bonding on hairpin stability. Investigation of 1H NMR melting curves of the diastereomeric compounds in a variety of solvents allowed an evaluation of the role of hydrophobic effects on secondary structure stabilization to be made.
- Erdelyi, Mate,Langer, Vratislav,Karlen, Anders,Gogoll, Adolf
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p. 834 - 843
(2007/10/03)
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- Enantioselective hydrolytic reactions of rice bran lipase (RBL): A first report
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Enantioselectivity has been observed in the hydrolysis of racemic N-acetyl amino acid esters with rice bran lipase (RBL). The enzyme shows selectivity towards the (S)-enantiomer. Products with high enantiomeric excess (e.e. >99%) are obtained depending upon the hydrophobicity of the amino acid as well as that of the leaving group.
- Fadnavis,Jadhav, Vasudev
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p. 2361 - 2366
(2007/10/03)
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- Cosmetic composition
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A composition suitable for topical application to mammalian skin and hair for inducing, maintaining or increasing hair growth comprises a hair growth promoter chosen from glutamine derivatives and salts thereof. The composition preferably also comprises an activity enhancer which may be chosen from hair growth stimulants, penetration enhancers and cationic polymers.
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- Cosmetic composition containing DOPA derivatives
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A composition for topical application to human hair or skin contains a chemical analogue of dihydroxyphenyl alanine (DOPA). This chemical analogue can be absorbed by skin or by a hair follicle and metabolised in-vivo, thus leading to the formation of melanin in skin or to the growth of melanin-pigmented hair. Consequently the composition can give controlled skin darkening to mimic sun-induced tanning or can bring about the growth of dar hair in place of the grey or white hair.
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- A novel tea-bag methodology for enzymatic resolutions of α-amino acid derivatives in reverse micellar media
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A novel tea bag methodology for resolution of methyl esters of N-acetyl- α-amino acids in reverse micellar medium of bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) in isooctane-chloroform using immobilized enzymes or microbial cells is presented. The methodology effectively solves the problems of substrate solubility, product separation and surfactant recycling and provides products in high yields (80 to 90%) and excellent optical purities (% ee 97 to >99%).
- Bhalerao,Rao,Fadnavis
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p. 2109 - 2118
(2007/10/02)
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- Cosmestic composition
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A composition suitable for topical application to mammalian skin and hair for inducing, maintaining or increasing hair growth comprises a hair growth promoter chosen from glutamic acid derivatives and salts thereof. The composition preferably also comprises an activity enhancer which may be chosen from hair growth stimulants, penetration enhancers and cationic polymers.
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- Hair growth composition containing citric acid esters
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Triesters of citric acid are used for inducing, maintaining or increasing hair growth. Compositions for topical application to mammalian hair or scalp comprise an effective amount of from 1% to 99% by weight of an ester of citric acid having the structure (1): where, R1, R2 and R3 each independently represent a branched or unbranched alkyl, alkenyl, aryl, alkylaryl or arylalkyl group, each said group having from 1 to 18 carbon atoms, R4 represents -H, or a branched or unbranched saturated or unsaturated acyl, alkyl, aryl, alkylaryl or aylalkyl group having from 1 to 18 carbon atoms, in the presence of a cosmetically acceptable vehicle for the citric acid ester and in the absence of solid absorbent for the ester;, said effective amount of said ester being sufficient to increase hair growth in the rat, when said composition is applied topically thereto over a period of no more than three months, by at least 10% more than that obtainable using a control composition from which the said ester has been omitted, in accordance with the Rat Hair Growth Test.
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- Acetylation under ultrasonic conditions: Convenient preparation of N-acetylamino acids
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An efficient and simple method of preparation of acetylamino acids from amino acids under ultrasonic conditions is described. The reactions proceed without racemization and the yields are almost quantitative.
- Veera Reddy,Ravindranath
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p. 257 - 264
(2007/10/02)
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- Cosmetic composition
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A composition suitable for topical application to mammalian skin and hair for inducing, maintaining or increasing hair growth comprises a hair growth promoter chosen from N-acylated amino-acids, in which the acyl group has from 2 to 20 carbon atoms, together with a cosmetically acceptable vehicle for the hair growth promoter.
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- Marine natural products. XXV. Biologically active tridecapeptide lactones from the Okinawan marine sponge Theonella swinhoei (theonellidae). Structure of theonellapeptolide Id
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Theonellapeptolide Id (1), a tridecapeptide lactone, was isolated from the Okinawan marine sponge Theonella swinhoei and the structure 1 was determined. A new HPLC analysis method for analyzing the amino acid composition of 1 containing N-methyl amino acids was devised.
- Kitagawa, Isao,Lee, Nam Kyung,Kobayashi, Motomasa,Shibuya, Hirotaka
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p. 2169 - 2180
(2007/10/02)
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- Efficient Asymmetric Hydrogenations of (Z)-2-Acetamidoacrylic Acid Derivatives with the Cationic Rhodium Complex of (2S,4S)-MOD-BPPM
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The preparation of (2S,4S)-MOD-BPPM ((2S,4S)-N-(t-butoxycarbonyl)-4-phosphino>-2-phosphino>methyl>pyrrolidine) and its application to highly effective asymmetric hydrogenations of (Z)-2-acetamidoacrylic acid derivatives are described.
- Takahashi, Hisashi,Achiwa, Kazuo
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p. 305 - 308
(2007/10/02)
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- ENANTIOSELECTIVE HYDROLYSIS BY BAKER'S YEAST - II. ESTERS OF N-ACETYL AMINO ACIDS
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D-N-Acetyl amino acid esters were obtained via enantioselective hydrolysis of their racemates by use of fermenting yeast.Evidence is given that proteinases are the enzymes involved.
- Glaenzer, B. I.,Faber, K.,Griengl, H.
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p. 771 - 778
(2007/10/02)
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- A general and accurate nmr determination of the enantiomeric purity of α-aminoacids and α-aminoacid derivatives
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Derivatization of α-aminoacids, α-aminoesters and α-aminolactones as N-acetyl derivatives allow the accurate NMR determination of the enantiomeric purity. In these conditions the major coordination site with a chiral shift reagent will correspond to the NMR observation site. Experimental factors leading to the highest ΔΔδ values are ascertained. No straightforward correlation with absolute configurations can be established.
- Calmes, Monique,Daunis, Jacques,Jacquier, Robert,Verducci, Jean
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p. 2285 - 2292
(2007/10/02)
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- NEW SYNTHETIC ROUTE TO N-ACYL-α-AMINO ACIDS VIA AMIDOCARBONYLATION BY MEANS OF HOMOGENEOUS BINARY CATALYST SYSTEMS
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New catalytic processes which lead to the formation of N-acyl-α-amino acids promoted by homogeneous binary systems are described: (a) the isomerization-amidocarbonylation of allylic alcohols catalyzed by transition metal binary systems, e.g., Co-Rh, Co-Pd, Co-Fe, giving various aliphatic N-acyl-α-amino acids; (b) the isomerization-amidocarbonylation of oxiranes catalyzed by cobalt-Lewis acid systems giving N-acyl-α-amino acids; The process is extremely effective for the synthesis of N-acetylphenylalanine from styrene oxide and (c) the hydroformylation-amidocarbonylation of trifluoropropene catalyzed by cobalt-rhodium binary system giving N-acetyltrifluorovaline in excellent regioselectivity and yield.Possible mechanisms for these new processes are discussed.
- Hirai, Kenji,Fujita, Makoto,Fuchikami, Takamasa
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p. 203 - 214
(2007/10/02)
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- DIRECT CONVERSION OF ALLYLIC ALCOHOLS INTO N-ACYL-α-AMINO ACIDS BY CATALYTIC AMIDOCARBONYLATION BY MEANS OF HOMOGENEOUS BINARY SYSTEMS
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N-Acyl-α-amino acids are synthesized by the amidocarbonylation of allylic alcohols catalyzed by homogeneous binary systems which consist of cobalt carbonyl and rhodium (or iron or palladium) complexes.
- Hirai, Kenji,Takahashi, Yoshitaka,Ojima, Iwao
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p. 2491 - 2494
(2007/10/02)
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