ライフサイエンスコーパス: chiral center

1 of a phenyl group positioned remote from the chiral center.

2 ntaining a bulky substituent adjacent to the chiral center.

3 table signs based on the substituents on the chiral center.

4 each of the four ligands around the reactive chiral center.

5 erienced by the porphyrin ring bound to each chiral center.

6 he phosphate ester backbone introduces a new chiral center.

7 ycloalkanoic groups positioned at the acidic chiral center.

8 Metabolism of NNK to NNAL produces a chiral center.

9 onformation and has S stereochemistry at the chiral center.

10 is most commonly associated with a localized chiral center.

11 the formation of an oxygenous cycle with one chiral center.

12 ties with or without a preexisting substrate chiral center.

13 sts that contain a synthetically challenging chiral center.

14 ed by chemical bond polarization involving a chiral center.

15 to a chiral pyridinium salt to set the first chiral center.

16 a chiral pyridinium salt to set the initial chiral center.

17 e molecular vibrations involving each of the chiral centers.

18 t adopt chiral folds, despite the absence of chiral centers.

19 erted to trisubstituted alkenes with allylic chiral centers.

20 hat generates cascade products with multiple chiral centers.

21 e organic synthesis to create molecules with chiral centers.

22 ligand leads to three newly created adjacent chiral centers.

23 y of cyclizations with substrates containing chiral centers.

24 end this four-carbon chain and introduce new chiral centers.

25 to form phosphatidic acids, nor do they have chiral centers.

26 to produce 1-tetralones with two contiguous chiral centers.

27 ding blocks are defined by a high density of chiral centers.

28 lar asymmetric communication between the two chiral centers.

29 ral ligands has been applied to control only chiral centers.

30 ion of stereo- and absolute configuration of chiral centers.

31 izing stems in part from the presence of two chiral centers.

32 reoisomers of a coupled product with vicinal chiral centers.

33 on to construct carbocycles containing three chiral centers.

34 ty in soft matter with no chemically induced chiral centers.

35 ) helps increase their variety by adding new chiral centers.

36 iolane ring leading to up to four contiguous chiral centers.

37 as a platform for the construction of alpha-chiral centers.

38 epimerization occurs at the vulnerable alpha-chiral centers.

39 were the compounds with two (S)- and two (R)-chiral centers.

40 y couple at their beta-positions, generating chiral centers.

41 complex substrates possessing more rings and chiral centers.

42 with pinpoint stereochemical control of both chiral centers.

43 ne products having in place three contiguous chiral centers.

44 lsulfones and gamma-phenylesters bearing two chiral centers.

45 e stereochemistry between the beta and delta chiral centers.

46 termined by the double bond geometry and the chiral center already present.

47 include the effect of position and number of chiral centers, amino acid order, and steric effects.

48 We incorporated an a-chiral center and an alkoxy alkene tether on the substra

49 idines exhibit chirality in the absence of a chiral center and axis.

50 The creation of the third chiral center and benzopyran ring is demonstrated with t

51 The methamphetamine molecule has a chiral center and exists as 2 enantiomers, d-methampheta

52 ent method to introduce the benzylic alcohol chiral center and obtain the desired chiral diol precurs

53 ion of an oxygen-containing tetrasubstituted chiral center and provide a new, general organocatalytic

54 Introduction of the second chiral center and subsequent chiral separations provided

55 soy isoflavones daidzein or genistein, has a chiral center and therefore can occur as 2 distinct dias

56 PSs without a chiral center and with an alkyl chain or thioether funct

57 gues based on a cyclohexane moiety with five chiral centers and a fused cyclopropyl ring have been sy

58 ormed into functionalized materials with two chiral centers and alpha,omega-groups that provide exten

59 The inhibitors contain only two chiral centers and are readily synthesized in optically

60 ular weight compounds (< 475) have one or no chiral centers and are readily synthesized.

61 In total, at least five chiral centers and four rings are generated by this mult

62 These introduce chiral centers and generate ON diastereomers.

63 eoselective manner, furnishing five adjacent chiral centers and leading to a single diastereoisomer o

64 Fenoterol contains two chiral centers and may exist as four stereoisomers.

65 to cyclopentanone scaffolds bearing multiple chiral centers and protected hydroxy groups.

66 Epoxyquinoids possess multiple contiguous chiral centers and reactive functional groups, offering

67 MBCHs generally contain one or more chiral centers and so two or more stereoisomeric forms a

68 rine and pseudoephedrine containing multiple chiral centers and the potential use of this amino-acid

69 of the relative stereochemistry between the chiral centers and the steric and electronic influences

70 e (all of the same configuration at the C-1' chiral center), and the diastereomer of the diethylamide

71 nduce symmetry into a monomethyl substituted chiral center, and (6) apply the Thorpe-Ingold conformat

72 tructures lacking the l-configuration at the chiral center, and those with polar substituents were es

73 symmetric epoxidation, which establishes the chiral centers, and a one-pot oxidative olefin cleavage/

74 hain extension substrates, the generation of chiral centers, and further functional group modificatio

75 their wide structural diversities, abundant chiral centers, and the relative ease with which their f

76 es of catalytic processes whereby all of the chiral centers are created with high stereoselectivities

77 measurements of stereoisomers with multiple chiral centers are essential yet challenging.

78 The absolute configurations of the chiral centers are established by using Burgess' enzymat

79 From this reaction, two chiral centers are generated, with absolute stereochemis

80 Molecules that possess fully substituted chiral centers are often challenging to construct, parti

81 The major amino acids with chiral centers are racemic within the accuracy of the me

82 lytic approaches to generate enantiospecific chiral centers are the major premise of modern organic c

83 The chiral centers are ultimately derived from commercially

84 nd carboxylic acid groups and a pre-existing chiral center, are ideal for making diverse and selectiv

85 the cyclohexane ring is constructed with two chiral centers as a single diastereomer with 97% ee.

86 ivation, shares the same scaffold with three chiral centers as the aforementioned compounds.

87 oselective, forming a tertiary or quaternary chiral center at an acetal or ketal carbon with good ste

88 With a pre-existing chiral center at any of the backbone sp(3)-carbons, the

89 l acyclic nucleoside phosphonates, 12 with a chiral center at C-2', and eight bearing a second chiral

90 l center at C-2', and eight bearing a second chiral center at C-6'.

91 d structures, however, possess an additional chiral center at C-6.

92 to Cys(24), the chromophore A-ring assumes a chiral center at C2, thus becoming 2(R),3(E)-phytochromo

93 or the vitamin D receptor (VDR) concerns the chiral center at carbon 20 of the steroid side chain; 20

94 ries of four indolenine squaraines bearing a chiral center at the 3-position of the indolenine moiety

95 Stereochemical consequences of a chiral center at the 4-position was evaluated, revealing

96 a pair of deuterated diastereoisomers with a chiral center at the benzylic position.

97 aryl or N-arylindolyl bridges along with one chiral center at the bridgehead carbon.

98 e scaffold (16) documented herein contains a chiral center at the heterocycle.

99 ereomeric CHF-BP conjugates, which feature a chiral center at the P(alpha)-CHF-P(beta) carbon, also e

100 This substitution creates a new chiral center at the phosphorus atom of the linkage.

101 tereoselectivity in the formation of the new chiral center at the phosphorus atom.

102 relies on two aldol reactions to install the chiral centers at C3/C4 and C3'/C4', a lithium-mediated

103 substituted glycines ("peptoids") containing chiral centers at the alpha position of their side chain

104 These compounds bearing two chiral centers, at position-1 in the ring and position-1

105 tive hydrazination to install the quaternary chiral center bearing a hydrazine moiety.

106 As glycine does not carry a chiral center, both (R)- and (S)-selective transaminases

107 hemistry of its previously unassignable C-37 chiral center, but which also was attended by the develo

108 chemical structure of the material shows no chiral centers, but suspensions of the nanotubes in an a

109 erful synthetic tool to introduce quaternary chiral centers, but the experimentally observed stereose

110 hiral amino acid derivatives with two remote chiral centers by borrowing hydrogen catalysis.

111 Since the parent amides bear two chiral centers (C-1 and C-1'), three of the better inhib

112 alkyl ether chain with a variable number of chiral centers, (c) hexyl ether versus thioether side ch

113 Both configurations of the beta-chiral center can be accessed by choosing the order in w

114 control over the stereochemistry at the new chiral center can be achieved.

115 azomethine ylides from which up to four new chiral centers can be generated via completed (3 + 2) cy

116 unity for stereocontrol at two noncontiguous chiral centers, carbon and phosphorus, leading to cyclic

117 Where the substituent itself possesses two chiral centers, comparison of the calculated isotropic s

118 lysis causes stereochemical inversion of the chiral center, converting a beta(R)-substrate to a beta(

119 (as measured by Fsp(3)) and the presence of chiral centers correlate with success as compounds trans

120 The elimination of a chiral center derived from the unnatural amino acid R-al

121 Thus the benzylic chiral center dictates the subsequent stereochemistry of

122 e, valine, and leucine as well as the single chiral center dipeptide surfactant poly(sodium undecyl-L

123 The novel stereospecific dual chiral-center-embedded structure of this compound has en

124 ptically active enol ether 6 bearing the C23 chiral center followed by a reductive ring contraction r

125 s of olefins are highly enantioselective for chiral centers formed during radical termination but poo

126 me and a potent experimental herbicide whose chiral center forms an essential part of the inhibitor p

127 Substitution of one chiral center from R(p) to S(p) has a profound effect on

128 l building blocks with enantioenriched alpha-chiral centers from this abundant C-4 skeleton.

129 R)- methyl-beta-alanine) in which the lactam chiral center has been removed.

130 ctionalized 1-halocyclopentenes with several chiral centers has been developed.

131 lic acids and derivatives that possess three chiral centers have been prepared in high yield and ster

132 a propyl group or introducing an additional chiral center improved cellular retention and tumor cell

133 helicity dictated by the substituents at the chiral center in accordance with their steric sizes (ass

134 the products possessing an alpha-quaternary chiral center in high enantioselectivities only in the c

135 es of aurachin natural products that has the chiral center in the alkyl side chain at C9'-position.

136 he oxazoline is not necessarily the dominant chiral center in the induction of selectivity.

137 the ligand and Tb(3+) ions, accompanied by a chiral center in the pores.

138 usual mode of enantioinduction by the remote chiral center in the transient directing group.

139 ite twists of nets 1 and 2, molecules with a chiral center in their rod-like core fail to follow the

140 blishing stereochemistry for four of the six chiral centers in (+)-desmethylxestospongin B.

141 d tetrahydroisoquinolines (THIQs) with three chiral centers in a step-efficient and selective manner

142 The stereochemistry of newly created chiral centers in aminocyclitols was established through

143 ection and quantitation of remotely disposed chiral centers in compounds in short supply.

144 accurate stereochemistry distinction for CF chiral centers in diastereomers.

145 ely functionalized compounds containing four chiral centers in just a one-pot sequence, the stereoche

146 to the formation of four C-C bonds and three chiral centers in one pot.

147 chemistry challenges presented by amino acid chiral centers in ProTides, a simplified lipophilic amin

148 The potential of chiral morphing (changing chiral centers in the ligands) to further refine the chi

149 irected toward probing the effect of the two chiral centers in the pyrrolidine ring on biological act

150 However, the introduction of chiral centers in the pyrrolidine rings in the course of

151 S-configured point chiral centers in the side chains transfer their chiral

152 o cyclic ketones featuring an alpha tertiary chiral center, including challenging 2-methylsuberone.

153 y of isoquinuclidines having five-contiguous chiral centers, including an all-carbon quaternary, were

154 The three required chiral centers, including two all-carbon quaternary chir

155 chiral starting material containing a single chiral center into the final target in a concise and dia

156 PS groups at varying positions may introduce chiral centers into the sgRNA backbone, resulting in a c

157 vailable, including the influence of the new chiral center introduced at the CHF carbon, as in beta,g

158 ule also dictates the stereochemistry of the chiral centers introduced into the backbone during the c

159 e affording 1-indanones with a C3-quaternary chiral center is also demonstrated.

160 Since the change in configuration of the chiral center is expected to change the distribution of

161 l-histidine complexation around the analyte chiral center is important for gas-phase stereoselectivi

162 center six atoms away from the newly forming chiral center is responsible for the diastereoselectivit

163 chiral heterocyclic compounds with adjacent chiral centers is achieved in enantiomeric ratios up to

164 ry in the spirobicyclic system bearing three chiral centers is initially set via a highly diastereose

165 c solutions, especially when the creation of chiral centers is involved.

166 sess a trans or cis relationship between the chiral centers is presented.

167 osition and R-configuration at the resulting chiral center, is attached by an ether linkage to the pr

168 es, with six fused rings and four contiguous chiral centers, is reported.

169 In this new lactone template, the two chiral centers must have the S-configuration for enzyme

170 3 (VRT-394), containing an inversion at the chiral center next to the alpha-ketoamide on exchange of

171 The quaternary chiral center of 3 was obtained by resolution of ethyl (

172 Each chiral center of poly SULL can have two possible configu

173 as racemates because of racemization at the chiral center of the 3-aminoglutarimide moiety.

174 with different absolute configuration at the chiral center of the aromatic residues in positions 3 an

175 In particular, the configuration of the C2 chiral center of the intermediate supports a model of th

176 The chiral center of the metamaterial is opened and emitters

177 The unique epimerization of the P-chiral center of the undesired (R,R)-diastereomeric phos

178 ones are formed with additional neighboring chiral centers of flexible stereochemistry in addition t

179 laisen rearrangement to set six of the seven chiral centers of strasseriolide B.

180 used as the key step for the control of the chiral centers of the central lignan core.

181 Chirality transfer is observed from the six chiral centers of the filled prisms to the single-handed

182 ation and allylation to generate half of the chiral centers of the molecule, whereas Negishi reaction

183 Proof of structure and configuration at all chiral centers of the nucleosides was obtained through a

184 The orientations of at least two chiral centers off the macrolide ring have no effect on

185 The effect of a chiral center on the biological activity was also invest

186 In the presence of a resident chiral center on the imine nitrogen, the use of a suitab

187 ate 18 followed by inversion of the adjacent chiral center on the morpholine ring.

188 ne spirocyclization of 35a and 35b, having a chiral center on the pendent side chain, was investigate

189 cycle from far-away-from to close-to a point-chiral center on the rotaxane axle changes the expressio

190 the addition pattern, not to the presence of chiral centers on the addends.

191 sulfated surfactants, poly-l-SUCILS with two chiral centers on the polymer head group provided overal

192 Due to the existence of several chiral centers on this molecule, upon the formation of [

193 s containing up to 12 individual C, S, or Au chiral centers per surface unit cell.

194 on, which involved the creation of three new chiral centers, proved to be diastereoselective, affordi

195 itions are derived inductively from a single chiral center provided by the commercially available Eva

196 eptafuran ring systems with three contiguous chiral centers, providing excellent diastereoselectivity

197 sis of pure active isomer 54, which has five chiral centers, required only seven steps from readily a

198 trate bonds through three side groups of the chiral center, respectively, which leads to significantl

199 d into the linker and full resolution of the chiral centers resulted in lead compound 53 and eutomer

200 spite the fact that the rhodium atom and the chiral center(s) are separated by more than 12 covalent

201 , the bilateral azapeptide products have two chiral centers separated by 14 atoms or 15 bonds, which

202 on and discriminate between enantiomers with chiral centers several carbons away from the binding sit

203 designed to explore the importance of TMQ's chiral center, showed a dramatic loss of potency (< 1%)

204 The sugar residue 5' to the S(p) chiral center shows A-form sugar puckering, with a C(3)(

205 linkers with opposite stereochemistry at the chiral center stabilize duplexes between the modified DN

206 action to set up two new rings and three new chiral centers stereoselectively.

207 For amino acids possessing two chiral centers such as dl-Ile or dl-Thr, only the epimer

208 e compounds contain one peptide bond and two chiral centers, suggesting that it may be feasible to in

209 These compounds all contain a single chiral center that is essential for inhibitory activity.

210 of azomethine imines, in which the substrate chiral center that is remote from the NHC catalyst can b

211 Between the two diastereomers of the PS RNA chiral center, the R(p) isomer is 37 times more active t

212 unctionalities were directly attached to the chiral center, the signs of the CD couplets were opposit

213 ary metabolite of atRA, 4-OH-RA, possesses a chiral center, the stereochemical course of atRA 4-hydro

214 fused rings (A to D) with three consecutive chiral centers, the last being created by the attachment

215 new carbon-carbon bonds and introducing two chiral centers, the resulting alkenylrhodium species und

216 enantioselective synthesis involving distant chiral centers through the formation of biomimetic super

217 oup in the unsymmetric pyrazoles generated a chiral center to extend the scope of this method.

218 diamines including those bearing an adjacent chiral center to the tertiary amine not easily achievabl

219 as tested and the contribution of the double chiral centers to this interaction was evaluated by use

220 Because oxiranyllithium has a chiral center, two diastereomeric dimers were formed, th

221 2,6-pyridinedicarboxamide) oligomer with six chiral centers using a lanthanide(III) ion template.

222 Herein we report a mild access to these chiral centers using cooperative gold(I) catalysis.

223 Construction of alpha-chiral centers via enantioselective C(sp(3))-H activatio

224 route, the requisite stereochemistry at the chiral center was generated at an early stage in the syn

225 The resulting chiral center was used to establish all remaining stereo

226 The absolute configuration at the new chiral centers was assigned through two-dimensional nucl

227 absolute configuration of the newly created chiral centers was definitively assigned for all the cor

228 elative stereochemistry at phormidolide's 11 chiral centers was established using the J-based configu

229 LSF, which has one asymmetric chiral center, was selectively inhibitory for IL-12 sign

230 ng the absolute stereochemistry at all eight chiral centers, was determined by a combination of spect

231 ecursors with a phenyl group attached at the chiral center were asymmetrically synthesized using a pe

232 ative and absolute stereochemistries at most chiral centers were assigned on detailed interpretation

233 tion, and the absolute configurations of new chiral centers were assigned.

234 al biopolymers of life would behave if their chiral centers were not configurationally stable, highli

235 ometry and the absolute configuration of the chiral centers were not determined.

236 lactones, while pentaketides with epimerized chiral centers were poorly processed by PikAIII-TE and f

237 ns of 1,n-glycols (n = 2-12, 16) bearing two chiral centers were rapidly determined via exciton-coupl

238 The three chiral centers were set by a combination of chiral auxil

239 igurations at both phosphorus and C-5 carbon chiral centers were unambiguously assigned.

240 ker O3'-CH(CH(3))-CO-NH-CH(2) (*designates a chiral center) were reported to lead to only a slight de

241 centers, including two all-carbon quaternary chiral centers, were built in the intramolecular Diels-A

242 e stereochemistry between the beta and gamma chiral centers when these are formed concurrently.

243 Poly SULL has two chiral centers which are defined by two asymmetric carbo

244 evented the access to fluorine-bearing alpha-chiral centers which are highly valuable in drug discove

245 with different stereochemistry at the second chiral center will produce all four possible isobaric en

246 Replacing the methyl group at the chiral center with a propyl group or introducing an addi

247 lacement of the exchangeable hydrogen at the chiral center with deuterium allows the stabilization an

248 hydroxyoxindoles carrying a tetrasubstituted chiral center with excellent yields and enantioselectivi

249 class that proceed through the creation of a chiral center with high asymmetric induction have been l

250 mediated Barbier allylation to set the third chiral center with high substrate control.

251 positions and proceeds at an enantioenriched chiral center with retention of stereochemistry.

252 (CAN) to establish the all-carbon quaternary chiral center with the proper configuration, and (d) an

253 exploited in the late-stage construction of chiral centers with aryl C-H bonds from aromatic feedsto

254 nnulation reaction efficiently generates 3/4 chiral centers with high diastereoselectivity.

255 is strategy, we constructed three contiguous chiral centers with high stereocontrol employing the sam

256 in a formal [3+3] cycloaddition to form four chiral centers with high stereocontrol.

257 ions, resulting in the formation of five new chiral centers with nearly absolute regio- and stereoche

258 Subsequent construction of chiral centers with readily available starting materials

259 ed materials, the ramifications of replacing chiral centers with stereodynamic atomic mimics in the c

260 ign is characterized by the incorporation of chiral centers within the endocannabinoid prototypes N-a

261 positions and proceeds at an enantioenriched chiral center without loss of enantiomeric excess.