59554-14-2Relevant academic research and scientific papers
N -Boc amines to oxazolidinones via Pd(II)/bis-sulfoxide/br?nsted acid Co-catalyzed allylic C-H oxidation
Osberger, Thomas J.,White, M. Christina
, p. 11176 - 11181 (2014/08/18)
A Pd(II)/bis-sulfoxide/Br?nsted acid catalyzed allylic C-H oxidation reaction for the synthesis of oxazolidinones from simple N-Boc amines is reported. A range of oxazolidinones are furnished in good yields (avg 63%) and excellent diastereoselectivities (avg 15:1) to furnish products regioisomeric from those previously obtained using allylic C-H amination reactions. Mechanistic studies suggest the role of the phosphoric acid is to furnish a Pd(II)bis-sulfoxide phosphate catalyst that promotes allylic C-H cleavage and π-allylPd functionalization with a weak, aprotic oxygen nucleophile and to assist in catalyst regeneration.
Chemoenzymatic formal total synthesis of (-)-bestatin
Feske, Brent D.,Stewart, Jon D.
, p. 3124 - 3127 (2007/10/03)
A highly stereoselective, enzymatic reduction of an α-chloro-β- keto ester provided the key intermediate for a total synthesis of the α-hydroxy-β-amino acid moiety of (-)-bestatin. The reduction product was cyclized to a glycidic ester that was opened in a Ritter reaction with benzonitrile, affording a trans-oxazoline, which was hydrolyzed under acidic conditions to the target molecule.
First one-pot copper-catalyzed synthesis of α-hydroxy-β-amino acids in water. A new protocol for preparation of optically active norstatines
Fringuelli, Francesco,Pizzo, Ferdinando,Rucci, Mauro,Vaccaro, Luigi
, p. 7041 - 7045 (2007/10/03)
α-Hydroxy-β-amino acids were synthesized with excellent yields for the first time in water and by a simple procedure based on a copper catalytic cycle, which included the recovery and reuse of the catalyst and is possible to realize by using only water as reaction medium.
Chirospecific synthesis of the (2S,3R)- and (2S,3S)-3-amino-2-hydroxy-4-phenylbutanoic acids from sugar: Application to (-)-bestatin
Lee, Jin Hwan,Lee, Byong Won,Jang, Ki Chang,Jeong, Ill-Yun,Yang, Min Suk,Lee, Sang Gyeong,Park, Ki Hun
, p. 829 - 836 (2007/10/03)
The enantiomerically pure (2S,3R)- and (2S,3S)-3-amino-2-hydroxy-4-phenylbutanoic acids (AHPBA) were first obtained from sugar in a chirospecific manner. Additionally, the obtained (2S,3R)-AHPBA 1 was easily applied to the synthesis of (-)-bestatin.
Asymmetric synthesis of 3-amino-2-hydroxy-4-phenylbutanoate
Ha, Hyun-Joon,Ahn, Young-Gil,Lee, Gwan Sun
, p. 2327 - 2336 (2007/10/03)
Asymmetric synthesis of 3-amino-2-hydroxy-4-phenylbutanoate, a key component of the natural product bestatin and HIV protease inhibitors of KNI- 272 and R-87366, has been achieved from the stereoselective aldimine coupling reaction between 3-phenyl-2-aminopropanenitrile and (Z)-α-methoxy trimethylsilyl ketene acetal in the presence of Lewis acids.
104. The enantioselective synthesis of β-amino acids, their α-hydroxy derivatives, and the N-terminal components of bestatin and microginin
Jefford, Charles W.,McNulty, James,Lu, Zhi-Hui,Wang, Jian Bo
, p. 1203 - 1216 (2007/10/03)
L-Aspartic acid by tosylation, anhydride formation, and reduction with NaBH4 was converted into (3S)-3-(tosylamino)butan-4-olide (8; Scheme 1). Treatment of 8 with ethanolic trimethylsilyl iodide gave the N-protected deoxy-iodo-β-homoserine ethyl ester 9. The latter, on successive nucleophilic displacement with lithium dialkylcuprates (→ 10a-e), alkaline hydrolysis (→ 11a-e), and reductive removal of the tosyl group, produced the corresponding 4-substituted (3R)-3-aminobutanoic acids 12a-e (ee >99%). Electrophilic hydroxylation of 8 (→ 19; Scheme 3), subsequent iodo-esterification (→ 21; Scheme 4), and nucleophilic alkylation and phenylation afforded, after saponification and deprotection, a series of 4-substituted (2S,3A)-3-amino-2-hydroxybutanoic acids 24 including the N-terminal acids 24e (= 3) and 24f (= 4) of bestatin and microginin (de >95%), respectively.
Diastereoselective Synthesis of 3-Amino-2-Hydroxyalkanoic Acid Derivatives
Kise, Naoki,Inakoshi, Naoto,Matsumura, Yoshihiro
, p. 909 - 912 (2007/10/02)
Both diastereomers of 3-amino-2-hydroxyalkanoic acid derivatives were synthesized selectively by LDA-induced reaction of N-methoxycarbonyl-1-methoxyamines with O-protected N,N-dimethylglycolamides.The inversion of the diastereoselectivity was highly achieved by 1) selecting the O-protecting groups and 2) the addition of Ti(OPr-i)4.
A novel synthesis of the (2R,3S)-and (2S,3R)-3-amino-2-hydroxycarboxylic acid derivatives, the key components of a renin inhibitor and bestatin, from methyl (R)- and (S)-mandelate
Kobayashi,Takemoto,Ito,Terashima
, p. 3031 - 3034 (2007/10/02)
The title synthesis could be accomplished by featuring the [2+2]-cycloaddition reaction of a chiral imine with benzyloxyketene, alcoholysis of the formed 2-azetidinone derivative, and reductive removal of the mandelate-derived benzylic oxygen by way of a 2-oxazolidone derivative.
A STEREOCONTROLLED SYNTHESIS OF (-)-BESTATIN FROM AN ACYCLIC ALLYLAMINE BY IODOCYCLOCARBAMATION
Kobayashi, Susumu,Isobe, Toshiyuki,Ohno, Masaji
, p. 5079 - 5082 (2007/10/02)
1,2-Asymmetric induction of iodocyclocarbamation is described by using allylamines 2 and 6 and the method has been succesfully applied to a stereocontrolled synthesis of bestatin.
Process for producing threo-3-amino-2-hydroxybutanoyl-aminoacetic acids, as well as novel intermediated therefor and process for producing them
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, (2008/06/13)
A process for producing threo-3-amino-2-hydroxybutanoylaminoacetic acids comprises the steps of allowing to react a starting compound represented by the general formula: STR1 wherein R1 represents a naphthyl or a group of the formula: STR2 in which R6 and R7 represent individually hydrogen, halogen, amino or a protected amino, hydroxy or a protected hydroxy, a lower alkoxy or a lower alkyl and R2 represents a protected amino, with a starting compound represented by the general formula: STR3 wherein R3 represents hydrogen or an ester residue, to obtain threo-3-protected amino-2-hydroxy-4-oxobutanoic acid or its ester represented by the general formula: STR4 wherein R1, R2 and R3 have the same meanings as above, and then reducing the same into threo-3-protected amino-2-hydroxybutanoic acid or its ester represented by the general formula: STR5 wherein R1, R2 and R3 have the same meanings as above, and further converting the above compound into 3-amino-2-hydroxybutanoic acid represented by the general formula: STR6 wherein R2 ' represents amino or a protected amino, thereafter condensing the same, in a conventional manner for forming a peptide coupling, with a compound represented by the general formula: STR7 wherein R4 represents an alkyl having 3-4 carbon atom or 3-guanidinopropyl, while previously protecting as required those groups not relevant to the reaction, and removing the protecting groups for the functional groups to produce threo-3-amino-2-hydroxybutanoylaminoacetic acids represented by the general formula: STR8 wherein R1 and R4 have the same meanings as above. This invention also provides the compounds represented by the general formula (III) as novel intermediates for the above aimed compounds and a process for producing the intermediates.
