117857-95-1Relevant articles and documents
Synthesis and reactions of a novel 3,4-didehydropyroglutamate derivative
Oba, Makoto,Nishiyama, Naohiro,Nishiyama, Kozaburo
, p. 776 - 777 (2003)
Some reactions such as catalytic hydrogenation, Diels-Alder reaction, cyclopropanation, dihydroxylation, and Michael addition of a novel 3,4-didehydropyroglutamate derivative, in which the carboxylic group is protected as an ABO ester, are examined and found to take place in a stereospecific manner giving 3- and/or 4-substituted pyroglutamate derivatives without loss of enantiomeric purity at the α-position.
Synthesis of cyclopropanes via organoiron methodology: Stereoselective preparation of cis-2-(2′-carboxycyclopropyl)glycine
Wallock, Nathaniel J,Donaldson, William A
, p. 4541 - 4543 (2002)
A stereoselective route to cis-2-(2′-carboxycyclopropyl)glycine has been developed. exo-Nucleophilic addition to the (bicyclo[5.1.0]octadienyl)iron(1+) cation establishes the relative stereochemistry at the cyclopropane ring and the α-stereocenter. Subsequent removal of the metal and cleavage of the cyclic diene gave the protected target 10, which upon hydrolysis gave 1.
Novel stereocontrolled approach to conformationally constrained analogues of L-glutamic acid and L-proline via stereoselective cyclopropanation of 3,4-didehydro-L-pyroglutamic ABO ester
Oba, Makoto,Nishiyama, Naohiro,Nishiyama, Kozaburo
, p. 8456 - 8464 (2007/10/03)
A new stereocontrolled approach to l-(carboxycyclopropyl)glycines (l-CCGs) and 3,4-methano-l-prolines, conformationally constrained analogues of l-glutamic acid and l-proline, respectively, was developed using a 3,4-didehydro-l- pyroglutamate derivative as a common chiral template. The unsaturated l-pyroglutamate derivative employed in this work is a novel chiral synthon in which the carboxyl functionality is protected as a 2,7,8-trioxabicyclo[3.2.1] octyl group (ABO ester). Stereospecific cyclopropanation of the olefin using diazomethane followed by appropriate functional group interconversion gave l-CCG-III and trans-3,4-methano-l-proline with complete stereocontrol. Synthesis of other diastereomers of l-CCG and cis-3,4-methano-l-proline was accomplished by alteration of the 3,4-methanoglutamic acid framework via carboxycyclopropanation of the olefin with sulfur ylide and subsequent Barton decarboxylation reaction of the original γ-carboxyl group included in the pyroglutamate skeleton.
Reactivity of (Bicyclo[5.1.0]octadienyl)iron(1+) Cations: Application to the Synthesis of cis-2-(2′-Carboxycyclopropyl)glycines
Wallock, Nathaniel J.,Donaldson, William A.
, p. 2997 - 3007 (2007/10/03)
The addition of carbon and heteroatom nucleophiles to (bicyclo[5.1.0]octadienyl)Fe(CO)2L+ cations 5 or 8 (L = CO, PPh3) generally proceeds via attack at the dienyl terminus on the face of the ligand opposite to iron to generate 6-substituted (bicyclo[5.1.0]octa-2,4-diene)iron complexes (11 or 13). In certain cases, these products are unstable with respect to elimination of a proton and the nucleophilic substituent to afford (cyclooctatetraene)Fe(CO)2L (4 or 7). Decomplexation of 13f, arising from addition of phthalimide to 8, gave N-(bicyclo[5.1.0]octa-3,5-dien-2-yl)phthalimide (19). Oxidative cleavage of 19 (RuCl3/NaIO4) followed by esterification gave the cyclopropane diester 22, which upon hydrolysis gave cis-2-(2′ -carboxycyclopropyl)glycine (CCG-III, 18) (eight steps from 4, 43% overall yield). This methodology was also utilized for preparation of stereospecifically deuterated CCG-III (d-18) and optically enriched (-)-18. Deprotonation of 22 resulted in cyclopropane ring opening to afford the benzoindolizidine (23).
Novel enantioselective synthesis of trans-α-(2-carboxycyclo-prop-1- yl)glycines: Conformationally constrained L-glutamate analogues
Demir, Ayhan S.,Tanyeli, Cihangir,Cagir, Ali,Nawaz Tahir,Ulku, Dincer
, p. 1035 - 1042 (2007/10/03)
D- and L-α-(2-carboxycycloprop-1-yl)glycines were synthesized from trans-1,3-di(2-furyl)propenone. Conversion of the double bond to a cyclopropane is followed by the formation of an oxime ether. Enantioselective reduction of the oxime ether, separation of diastereomers and oxidation of the furane rings gave enantiomerically pure D- and L-CCG I and CCG II. The structure of oxime 7b was determined by X-ray crystal structure analysis. The key step is the oxazaborolidine catalyzed enantioselective conversion of oxime ethers to amines.
Facile synthesis of (2S,1'S,2'S)-2-(carboxycyclopropyl)glycine an isotype-selective agonist of metabotropic glutamate receptors
Ma, Dawei,Ma, Zhaochun
, p. 7599 - 7602 (2007/10/03)
(2S,1'S,2'S)-2-(Carboxycyclopropyl)glycine (L-CCG-I) was synthesized in 12 steps and 14% overall yield by using Sharpless's asymmetric dihydroxylation reaction and stereochemically controlled cyclopropanation as key steps.
Study of the reactivity profile of glycine Schiff's bases with dipolarophiles: Application towards a concise synthesis of CCG-II
Chavan, Subhash. P.,Venkatraman,Sharma, Anil. K.,Chittiboyina, Amar Gopal
, p. 2857 - 2858 (2007/10/03)
The reactivity profile of glycine Schiff's bases with crotonate and bromocrotonate has been shown to take a different course depending on the choice substituent on the imine. Application of the above study for the mild and concise synthesis of CCG-II has been achieved.
Synthesis of Four Diastereomeric L-2-(Carboxycyclopropyl)glycines. Conformationally Constrained L-Glutamate Analogues
Shimamoto, Keiko,Ishida, Michiko,Shinozaki, Haruhikio,Ohfune, Yasufumi
, p. 4167 - 4176 (2007/10/02)
To determine what conformations of L-glutamate (L-Glu) activate that compound's different receptors in the mammalian central nervous system, four diastereochemically L-2-(carboxycyclopropyl)glycines, 1-4, which are conformationally constrained analogues o
D-3,4-'cyclopropylglutamate' isomers as nmda receptor ligands: Synthesis and enantioselective activity
Pellicciari, Roberto,Natalini, Benedetto,Marinozzi, Maura,Monahan, Joseph B.,Snyder, James P.
, p. 139 - 142 (2007/10/02)
Dirhodium(II) tetraacetate catalyzed decomposition of ethyl diazoacetate in the presence of D-Cbz-vinylglycine methyl ester (11) afforded a mixture of the cyclopropyl esters D-CGA A-D (13) from which the corresponding 2R-acids 7-10 were obtained and their absolute configurations assigned. The (2R,3S,4R) α-(carboxycyclopropyl)glycine (D-CGA C, 9 resulted to be the most potent and selective among the NMDA receptor ligands yet reported.
