ライフサイエンスコーパス: chiral center

1 sts that contain a synthetically challenging chiral center.

2 he phosphate ester backbone introduces a new chiral center.

3 ycloalkanoic groups positioned at the acidic chiral center.

4 Metabolism of NNK to NNAL produces a chiral center.

5 onformation and has S stereochemistry at the chiral center.

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

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

8 ntaining a bulky substituent adjacent to the chiral center.

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

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

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

12 y of cyclizations with substrates containing chiral centers.

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

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

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

16 epimerization occurs at the vulnerable alpha-chiral centers.

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

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

19 with pinpoint stereochemical control of both chiral centers.

20 ne products having in place three contiguous chiral centers.

21 lsulfones and gamma-phenylesters bearing two chiral centers.

22 e stereochemistry between the beta and delta chiral centers.

23 e molecular vibrations involving each of the chiral centers.

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

25 erted to trisubstituted alkenes with allylic chiral centers.

26 hat generates cascade products with multiple chiral centers.

27 ligand leads to three newly created adjacent chiral centers.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

55 The chiral centers are ultimately derived from commercially

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

77 Thus the benzylic chiral center dictates the subsequent stereochemistry of

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

107 3 (VRT-394), containing an inversion at the chiral center next to the alpha-ketoamide on exchange of

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

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

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

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

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

113 The chiral center of the metamaterial is opened and emitters

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

144 2,6-pyridinedicarboxamide) oligomer with six chiral centers using a lanthanide(III) ion template.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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