ライフサイエンスコーパス: racemization

1 mismatch with similar affinities and without racemization.

2 merization barriers were obtained by thermal racemization.

3 roceeds effectively, with very low levels of racemization.

4 substituted oxetan-3-ones without detectable racemization.

5 thod is simple, high-yielding, and free from racemization.

6 d hydrolysis products in high yields with no racemization.

7 rresponding chiral amines without detectable racemization.

8 to give the key chiral intermediate without racemization.

9 orresponding unsaturated amino acids without racemization.

10 longer reaction times, the catalyst effects racemization.

11 n without undergoing thermal or photoinduced racemization.

12 s of the rates or mechanisms of halonium ion racemization.

13 minoxy peptides 10a,b in good yields without racemization.

14 promiscuous, catalyzing both dehydration and racemization.

15 ees C for several months without any sign of racemization.

16 mino acid derivatives with mimimal levels of racemization.

17 zed by the wild-type enzyme exceed those for racemization.

18 The second step was assigned to complex racemization.

19 hat metalation leads to a much lower rate of racemization.

20 yield under mild conditions with no signs of racemization.

21 rt-bound ACC in good yields and with minimal racemization.

22 n of configuration with no detectable (< 6%) racemization.

23 e linkages into pseudopeptide chains without racemization.

24 lized effectively through elevated levels of racemization.

25 riety of amino acid side chains with minimal racemization.

26 h-Gilbert homologation is optimized to avoid racemization.

27 ation could be applied to dipeptides without racemization.

28 tly couples Fmoc amino acids without notable racemization.

29 gnificant influence on the rate of substrate racemization.

30 of alcohols, a reaction relevant to lactate racemization.

31 iral 2-arylbutyrate and potentially prone to racemization.

32 acts as the catalytic acid during l-alanine racemization.

33 ion, at which point the preference is toward racemization.

34 ersion proceeds with good yield and shows no racemization.

35 ubstrates and furnished products without any racemization.

36 enantiopure amine starting materials without racemization.

37 ully coupled in good yields with very little racemization.

38 drug molecules is hampered by rapid in vivo racemization.

39 mainly as a result of its ability to prevent racemization.

40 Searching for strategies to avoid racemization, a new class of light-driven molecular moto

41 loped silk dating technique using amino acid racemization (AAR) in conjunction with capillary electro

42 The Y265F mutant reduces racemization activity 1600-fold and only leads to format

43 e other hand, the S84T (which performs l-Ser racemization activity), S84A (good kcat but high Km for

44 o sonication at 0 degrees C resulted in >95% racemization after 24 h, as determined by circular dichr

45 e they exhibit sufficiently high barriers to racemization after ortho functionalization.

46 The inclusion of a biocatalytic racemization along with the PAM-catalyzed reaction moder

47 ffraction (SAXS), amino acid composition and racemization analyses.

48 ted, formally neutral state for catalysis of racemization and beta-elimination.

49 The dynamics of the racemization and catalytic and stoichiometric dynamic re

50 work, we identify that the interplay between racemization and crystal growth rates elicits this surpr

51 has been developed by coupling incompatible racemization and crystallization processes.

52 e value of the free energy of activation for racemization and deuterium exchange was calculated to be

53 Racemization and epimerization processes are often obser

54 lable, and reproducible stereoisomerization (racemization and epimerization) protocol for the prepara

55 ituents at N3 were found to suppress the C-5 racemization and in this way enabled the transfer of chi

56 roles for each of the two catalytic bases in racemization and inactivation, as well as the importance

57 ated temperatures, quantifying the extent of racemization and peptide bond hydrolysis using reverse-p

58 y morphometry of fossils dated by amino acid racemization and radiocarbon.

59 tetramethylethylenediamine (TMEDA) for both racemization and resolution of the title compound and th

60 sented that accounts for both base-catalyzed racemization and thioether formation at the hinge disulf

61 of L-tyrosine was optimized to avoid partial racemization and to allow a more efficient scale-up.

62 cted on a substrate incapable of competitive racemization, and accommodates the convergent preparatio

63 adienylruthenium catalysts were used for the racemization, and lipase PS-IM or CALB was employed for

64 o 9) on neat samples is irreversible without racemization, and the alumina-mediated equilibration is

65 reversed ester analogues were impervious to racemization, and their chemically distinct branches fac

66 odification sites should exhibit significant racemization as a side reaction to the main repair pathw

67 th serine and asparagine are able to undergo racemization as internally bound residues, which shows t

68 chirality, rotation about that axis leads to racemization as the system reaches equilibrium.

69 phenyl phosphines are shown to undergo rapid racemization at ambient temperature when exposed to cata

70 hiohydantoins turned out to be more prone to racemization at C-5 during the ring formation.

71 s developed and sold as racemates because of racemization at the chiral center of the 3-aminoglutarim

72 , and asparagine (Asn) did not show signs of racemization at the irradiation times studied; however,

73 The reaction proceeds without racemization at the stereogenic center of the amino acid

74 and (M)-TBBA atropisomers were stable with a racemization barrier above 30 kcal/mol.

75 h the experimental geometry and the observed racemization barrier for 2 are in good agreement with co

76 We estimated that the racemization barrier for the two cyclochiral conformers

77 determination of absolute configuration and racemization barrier is also reported.

78 The theoretical study of the racemization barrier suggested a reasonable shift toward

79 The N-C racemization barrier was found to be bigger than 25 kcal

80 computed barriers are in good agreement with racemization barriers estimated from existing experiment

81 dies demonstrate that the magnitude of their racemization barriers is primarily determined by the ide

82 The new helicenes possess low racemization barriers, as demonstrated by dynamic (1)H N

83 ve inversion experiments are used to measure racemization barriers.

84 n atom followed a retentive course with some racemization because of the involvement of a benzyllithi

85 mon step, their overall reactions (including racemization, beta-elimination of water, beta-eliminatio

86 0(5) M(-1) s(-1) for catalysis of amino-acid racemization by alanine racemase shows that the enzyme c

87 y, longer, compressed alkanes accelerate the racemization by applying pressure from the inside on the

88 stabilizing the planar transition state for racemization by approximately 40 kJ mol(-1) , thereby fa

89 aziridine enantioenriched and monitoring its racemization by CD spectroscopy.

90 ne formation, establishing minimal competing racemization by deprotonation.

91 isopropylbenzyl alcohol) also accelerate the racemization by facilitating the rotation of the glycolu

92 e beta-lactam framework was possible without racemization by treatment with SmI2.

93 t exist as a mixture of four isomers undergo racemization by two orthogonal mechanisms and are conver

94 It has been postulated that racemization can occur rapidly dependent on several fact

95 o the incompatibility of the ruthenium-based racemization catalyst with the acylating agent (Ac(2)O)

96 If the facile process of radical racemization could be effectively combined with an ensui

97 p51, a comparison site, exhibited negligible racemization (D/L < or = 0.01).

98 25 in wild type mice, but substantially less racemization (D/L = 0.035) at Asp25 in PIMT-deficient mi

99 efficient decreased further to 0.58 when the racemization data from all mammals (including human) wer

100 ts support species specificity of amino acid racemization dating.

101 of the l-enantiomer either to d-enantiomer (racemization), degradation to undesired products or taut

102 s, amino acid analysis, protein analysis and racemization degree, for assessing their potential for f

103 ide (l-)L2 showed that the isomerization and racemization did not occur, indicating that the Asp degr

104 ic methine-containing compounds are prone to racemization driven by keto-enol tautomerization, which

105 inely used in peptide chemistry for reducing racemization due to the increased reactivity.

106 The racemization energy of 1d is more than 12 kcal.mol(-1) s

107 Incorporation of a strap can slow racemization even further.

108 Racemization experiments show that phosphinic acid does

109 The rate of racemization for amides 54-57 is strongly dependent on t

110 ne and the development of effective and near-racemization free conditions for esterification of its h

111 ne and the development of effective and near-racemization free conditions for esterification of its h

112 ge in the final coupling reaction under near racemization free conditions.

113 9 was prepared by de novo synthesis using a racemization-free fragment coupling method.

114 A general and robust racemization-free protocol for the synthesis of a variet

115 This synthesis also features the racemization-free reductive removal of the chiral auxili

116 The racemization half-life of a compound within this series

117 Racemization has a large impact upon the biological prop

118 S-(Pg-alpha-aminoacyl)tripeptide 14 without racemization in 47-90% yields using N-(Pg-alpha-aminoacy

119 e of compounds with known rate constants for racemization in aqueous conditions was hitherto limited.

120 uilding blocks in a multistep system without racemization in excellent yields.

121 alogously to the alpha-amino esters, without racemization in high yields under mild conditions.

122 re we determine the genetic basis of lactate racemization in Lactobacillus plantarum.

123 -arylphosphine boranes were obtained without racemization in moderate to good yields and with ee up t

124 e performed to elucidate a new mechanism for racemization in Prins cyclization reactions.

125 e crystals for which the enantiomers undergo racemization in solution.

126 sine and do not show a propensity to undergo racemization in vitro.

127 A combination of degradation or amino acid racemization inhibition of trypsin digestion appears to

128 coupling products can be transformed without racemization into enantioenriched alpha-arylcarboxylic a

129 rylation of chiral alpha-aminoesters without racemization, involving Buchwald-Hartwig conditions.

130 y calculations indicate that the barrier for racemization is 9.9 kcal/mol, so the barrier for allylat

131 paddle size and only when the time scale for racemization is comparable to the time scale for segment

132 Racemization is considered to be an intrinsic stereochem

133 ned, and the abundance of deamidation-linked racemization is examined.

134 Lactic acid racemization is involved in lactate metabolism and cell

135 The racemization is limited by the polymer matrix only for p

136 In nonpolar solvents, however, the substrate racemization is primarily uncatalyzed.

137 fluoren-9-yl acrylate) [poly(BBPFA)], as its racemization is selectively driven by light without any

138 ally more hindered amides 23-24, the rate of racemization is significantly reduced.

139 The high barrier for this racemization is unique in probe studies of glasses and c

140 The degree of the racemization is, however, affected by the silane/carbony

141 er 231 and to a lower extent at Ser 229; and racemization/isomerization of l-Asp 243 to d-Asp and d-i

142 lens indicated an increase in truncation and racemization/isomerization with fiber cell age, whereas

143 ctical synthetic strategy was developed, and racemization issues were addressed using diastereomeric

144 yl paddles of varying sizes and studying the racemization kinetics as a function of temperature.

145 ormational isomers, and the determination of racemization kinetics of CD active chiral compounds.

146 iew of the role of segmental dynamics on the racemization kinetics of the binaphthyls and allow the i

147 Detailed information on racemization kinetics was collected for the most stable

148 ons, and the three-dimensional structure and racemization kinetics were studied by crystallography an

149 iate alpha-sulfonyl anion is more rapid than racemization, leading to a highly enantiospecific proces

150 We show that rate constants for racemization (measured by ourselves and others) correlat

151 c enantioselective HPLC (D-HPLC), or kinetic racemization measurements.

152 These results support a two-base racemization mechanism involving Y265 and K39.

153 iments excluded the possibility of a thermal racemization mechanism.

154 This new racemization method solves the problem of (enantioselect

155 will be dedicated to the design of efficient racemization methods as an important means of developing

156 silks" showed excessive levels of amino acid racemization not only for aspartic acid, but also for ph

157 catalyze both OSBS and N-succinylamino acid racemization (NSAR).

158 alyze another reaction, N-succinylamino acid racemization (NSAR).

159 We also propose that the racemization observed with 1,1'-carbonyldiimidazole (CDI

160 No racemization occurred when the procedure was applied to

161 The racemization occurs by a simple one-dimensional twisting

162 Racemization occurs due to imine formation at the chiral

163 Here, we report that racemization occurs on both H220 and L214 on an IgG1 wit

164 Racemization occurs via an inversion-rotation process.

165 into the alpha-position of mandelate and the racemization of (R)-mandelate, after samples had been in

166 kcal/mol is estimated for the photochemical racemization of 1-methanesulfinylpyrene.

167 lind spot, we have measured the kinetics for racemization of 28 compounds using circular dichroism an

168 ation occurring in a chain-type fashion with racemization of a Cu(I) homochiral dimeric intermediate,

169 orward NMR method to establish the degree of racemization of activated esters of Boc-Ala or amide bon

170 of alcohols with an active catalyst for the racemization of alcohols did not lead to DKR, due to the

171 In addition, nonenzymatic racemization of allantoin has been shown to occur at phy

172 In addition, this exchange reaction leads to racemization of allylic amines.

173 Racemization of amino acids is a common chemical degrada

174 nding of this study is that the mechanism of racemization of an alanine zwitterion in water is altere

175 Here we report the first study on racemization of an intrinsically chiral gold nanocluster

176 nd anabolic dehydrogenases to perform D-to-L racemization of arginine, which serves as prerequisite o

177 t that DauA and DauB are required for D-to-L racemization of arginine.

178 Parchment and rabbit skin glue exhibited racemization of Asp, as well as racemization of isoleuci

179 Racemization of Asp25 was independent of animal age over

180 In this work, we have used the racemization of aspartic acid as a marker for the turnov

181 In this study, we have quantified the racemization of aspartic acid to calculate the age of th

182 e in a particular tissue can, along with the racemization of aspartic acid, be used as a reliable mea

183 enabled by the observation that the rate of racemization of atropisomeric naphthamides is significan

184 this key step did not cause any measurable C-racemization of boranophosphorylated amino acids 22.

185 The dependence of kcat on pH for the racemization of both (R)- and (S)-mandelates suggests th

186 of the three subunits, to prevent late stage racemization of carboxylate-activated phenylglycine-deri

187 ring an N-heterocyclic carbene ligand in the racemization of chiral alcohols is reported.

188 elimination may provide a mechanism for the racemization of chiral alcohols, which would undermine a

189 e-based mechanism for the ruthenium-mediated racemization of chiral alcohols.

190 thods, demonstrating that the intramolecular racemization of Delta and Lambda enantiomers of d0 Ti(IV

191 measurement system for the kinetic study of racemization of dynamic chiral molecules was developed.

192 characterized and are known to catalyze the racemization of free proline or trans-4-hydroxyproline.

193 Glutamate racemase (MurI) catalyzes the racemization of glutamate; two cysteine residues serve a

194 ue exhibited racemization of Asp, as well as racemization of isoleucine (Ile) and phenylalanine (Phe)

195 Activation parameters for the racemization of K2[Ti2(3)] (H(2)2 = 2,3-dihydroxy-N,N'-d

196 cocci expressing the VanC phenotype involves racemization of L- to D-serine by a membrane-bound serin

197 n a soluble enzyme that catalyzes the direct racemization of L-serine to D-serine.

198 two distinct isomerization processes: faster racemization of mer-[Ti4(3)]2- by way of a Bailar twist

199 covered based on its ability to catalyze the racemization of N-acylamino acids (N-acylamino acid race

200 xadiene-1-carboxylate but also an accidental racemization of N-acylamino acids.

201 SBS from Amycolaptosis also can catalyze the racemization of N-acylamino acids.

202 Full racemization of poly-1b at +80 degrees C in toluene requ

203 Biosynthesis of D-amino acids from racemization of predominant L-enantiomers is catalyzed b

204 The facile racemization of protein-bound amino acids plays an impor

205 These data strongly support a stepwise racemization of stereoisomeric aldimine intermediates in

206 nantiomeric conformations with half-lives of racemization of t1/2 = 4150-25100 seconds at room temper

207 al catalytic roles, mediating both the rapid racemization of the 5-aryl dioxolanediones and the enant

208 of conditions under which the formation and racemization of the allyl iodide occurs.

209 ) due to the P-chirogenic center but without racemization of the amino acid or peptide moiety.

210 etic route, optimizing this process to avoid racemization of the azide intermediate, finally yielding

211 s proceed through a facile catalyst-mediated racemization of the beta-bromo-alpha-keto esters under a

212 At ambient temperature, racemization of the beta-position through a putative rev

213 n of the enantiomers allowed us to study the racemization of the chiral cluster, which reflects the f

214 The coalescence effects are assigned to racemization of the chiral ground-state conformation wit

215 degradation pathways, the first of which is racemization of the chiral sulfonium group, which takes

216 of the allylic alcohol side product and the racemization of the chirally unstable alpha-substituted

217 operties and free energies of activation for racemization of the garuganin and garugamblin diarylethe

218 Similar conditions also result in racemization of the H220 cysteine.

219 Racemization of the optical antipodes of these compounds

220 the capsule as inferred from monitoring the racemization of the optically pure alpha-alkyl deoxybenz

221 Racemization of the original N-terminal Asp to l-isoAsp

222 riers to rotation, DeltaG(rot), that prevent racemization of the respective enantiomers.

223 scaffold leading to THIQ 40 and showcase the racemization of the scaffold, pharmacokinetic studies in

224 The racemization of the stacks follows first-order kinetics

225 were included in the reaction mixture, rapid racemization of the starting material occurred allowing

226 oceeds via an S(N)2 pathway, and the partial racemization of the starting substrate was effectively c

227 group conversions in high yields without any racemization of the stereogenic benzodioxane C(2).

228 factor, likely the barrier to isomerization/racemization of the tartaric acid, which is hypothesized

229 acids may gauge its extent by the consequent racemization of their ee.

230 xperimental and computational studies on the racemization of these enolates, we have studied the ring

231 ible thermal bond homolysis at 95 degrees C; racemization of these metallacycles is also catalyzed by

232 he use of photoredox catalysis to enable the racemization of traditionally static, unreactive stereoc

233 DFT calculations show on the example of the racemizations of binaphthyl compounds that pure unmodifi

234 These data and a dependence of alkoxide racemization on [PPh(3)] showed that the elementary beta

235 g and mechanisms of amino acid synthesis and racemization on asteroidal parent bodies is key to demon

236 ndence of rate, isotope effect, and alkoxide racemization on phosphine concentration revealed unusual

237 exible optically active solutes undergo fast racemization (on the NMR timescale) their spectrum corre

238 vacuum at elevated temperatures without any racemization or decomposition.

239 e alpha-formyl vinylic stereocenters without racemization or olefin transposition.

240 hexenes at all levels of conversion, with no racemization or symmetrization taking place during the c

241 the case for interconversion of enantiomers (racemization) or exchange of enantiotopic sites in isotr

242 instein rearrangement can be enlisted as the racemization pathway in a dynamic kinetic resolution of

243 s enantio-enriched products and to study the racemization pathway of chiral 1,2-disubstituted adamant

244 ortance of Y265 in both the inactivation and racemization pathway.

245 llenging because of their near-instantaneous racemization (picosecond timescale)(10).

246 The racemization proceeds by a multistep mechanism that is p

247 ure process was contributing to the observed racemization process accounting for the lower barriers i

248 probing of the helical self-assembly and the racemization process of these pi-conjugated OPV chromoph

249 Uncatalyzed racemization processes in atropisomeric diphenyl-like fr

250 ed at pH 6.9 and 8.9 from global analysis of racemization progress curves.

251 ), which enables the asymmetric synthesis of racemization-prone alpha-arylketones.

252 ch as N-terminal degradation, isomerization, racemization, pyroglutamyl formation, oxidation, and cov

253 Using the racemization rate found previously for the stable popula

254 The racemization rate is strongly dependent on the number of

255 ntly developed dating technique based on the racemization rate of aspartic acid was applied to dating

256 ur results interestingly indicated different racemization rates for specific amino acid residues.

257 henylalanine and tyrosine, inconsistent with racemization rates of these amino acids in authentic his

258 c solution would support rapid synthesis and racemization rates on the order of years, suggesting tha

259 imation of silk textiles based on amino acid racemization rates.

260 silanes as a stereochemical probe results in racemization rather than inversion of the configuration

261 In addition, the aspartic acid racemization ratio of this specimen was also consistent

262 The results imply that the racemization ratios of aspartic acid, phenylalanine, and

263 A racemization reaction between 17alpha-estradiol and 17be

264 he carbon acidity enhancement in the alanine racemization reaction catalyzed by alanine racemase (Ala

265 the reason that this enzyme is capable of a racemization reaction on these substrates, whereas the o

266 tion of the alpha-proton in the (R)- and (S)-racemization reactions, respectively.

267 rculated to the crystallizer in a resolution-racemization-recycle (R(3)) process.

268 The first racemization-stable helicene derivatives fluorinated at

269 to a binding pattern that resembles the post-racemization state of the other enantiomer, i.e., each e

270 nantiomerization were determined by off-line racemization studies and/or by treatment of the plateau-

271 Racemization studies employing a series of sterically di

272 ly by means of dynamic HPLC measurements and racemization studies.

273 Simply derivatize your amino acids with a racemization tag that incorporates a urea bond on the N-

274 The racemization tags investigated were 6-aminoquinolyl- N-h

275 This racemization takes place at modest temperatures (40-80 d

276 oping leads to a substantial lowering of the racemization temperature.

277 er rate constants for general-base-catalyzed racemization that are usefully accurate.

278 A destructive BINOL racemization that competes with the enantioselective oxi

279 nantiopurity of CHDTN(Tos)(2) due to partial racemization that occurs during the derivatization step.

280 A racemization time of 30 min at 95 degrees C will lead to

281 a method that leverages a cyclic iminium ion racemization to achieve dynamic kinetic resolution in an

282 of the enantiomers has allowed the rates of racemization to be measured and hence the free energy ba

283 ium chloride) or protic solvents, can induce racemization, too.

284 in glue showed a significant increase in Asp racemization upon increasing irradiation time with rabbi

285 on of the borane was easily achieved without racemization using DABCO to obtain the free o-halogeno-a

286 result of a temperature change; therefore, a racemization via disassembly assembly is proposed.

287 Likewise, racemization was detected at significant levels on H220

288 The inversion barrier for racemization was determined experimentally to be 29 kcal

289 No racemization was observed during this reaction.

290 rmined by circular dichroism; no appreciable racemization was observed in low-molecular-weight deriva

291 Good yields without racemization were achieved under milder and simpler reac

292 tivation barriers (DeltaG(double dagger)) of racemization were determined.

293 The kinetics of GaSz racemization were followed by selective, double spin-ech

294 l modeling support a novel mode of sulfoxide racemization which occurs via a rhodium pi-allyl interme

295 The previously observed racemization, which occurred during the synthesis of fla

296 -role catalyst and accelerates the substrate racemization while catalyzing olefin hydrogenation.

297 he calibration curve showed a slower rate of racemization with a lower correlation (0.88).

298 ielded CBL(P113S), which catalyzes l-alanine racemization with a poor Km (58 mm) but a high kcat (22

299 The oxyacylation products are also prone to racemization without catalyst when heated alone; however

300 ological value, the calculations reveal that racemization would be sufficiently fast to render these