ライフサイエンスコーパス: quaternary carbon

1 lenging reductive elimination that affords a quaternary carbon.

2 clobutanol to a spirocyclic indene bearing a quaternary carbon.

3 d products are formed with a new stereogenic quaternary carbon.

4 involve the construction of two 1,3-related quaternary carbons.

5 the communesin relative configuration at the quaternary carbons.

6 multiple stereocenters, including contiguous quaternary carbons.

7 ing complex carbon fragments and forming new quaternary carbons.

8 llowed for the enantioselective synthesis of quaternary carbons.

9 fragments with concomitant formation of new quaternary carbons.

10 re obtained with Et(3)N for the migration of quaternary carbons.

11 Its tetracyclic skeleton contains three quaternary carbons and is marked by several syn-pentane

12 rds tricyclic indolizidines that incorporate quaternary carbons and up to five stereocenters with goo

13 beta-Ketonitriles bearing a quaternary carbon at the 2-position were prepared throug

14 It was shown that NAs with a quaternary carbon at the alpha- or beta-position or a te

15 l with 2,3-butadienoates and amines having a quaternary carbon at the alpha-position.

16 Alkenes bearing quaternary carbons at the allylic or homoallylic positio

17 an alkyl group that possesses a tertiary or quaternary carbon atom alpha to the carbon-zirconium bon

18 tes of esters, to form products containing a quaternary carbon atom at the nucleophile moiety and a t

19 of amphiphiles, each built around a central quaternary carbon atom derived from neopentyl glycol, wi

20 ontaining two or more contiguous stereogenic quaternary carbon atoms and key reactions in their total

21 ituted oxindoles have one or more asymmetric quaternary carbon atoms and they represent a large famil

22 t contain two or more contiguous stereogenic quaternary carbon atoms in their intricate structures ar

23 ter, complex ring structure, the presence of quaternary carbon atoms, and the low number of functiona

24 yl- and pivalyl-CoA, possessing tertiary and quaternary carbon atoms, respectively, are discussed.

25 ing a bond between two sterically encumbered quaternary carbon atoms.

26 [2 + 2] adducts with all-carbon-substituted quaternary carbon atoms.

27 enolate C-allylation to introduce the second quaternary carbon center (C8), and an azide reduction/N-

28 Allylboronates that bear a quaternary carbon center are air-stable and can be easil

29 Functionalized cyclopentanes containing a quaternary carbon center are derived from alkylidene oxi

30 ludes examples containing a bridgehead sp(3) quaternary carbon center as well as the cycloisomerizati

31 lds containing a prochiral dienone system, a quaternary carbon center connected to as many as four sp

32 a functionalized dienone system containing a quaternary carbon center connected to several sp(2) cent

33 give dihydroindolizines 8 and 9 possessing a quaternary carbon center in good yield.

34 bonds, two new stereogenic centers, and one quaternary carbon center in one single operation, which

35 r the stereoselective generation of a chiral quaternary carbon center in the alkaloid scaffold is int

36 resulting in the formation of a challenging quaternary carbon center is also described.

37 red acyclic products embedding a methyl-aryl quaternary carbon center with up to 90% yield and 97:3 e

38 aring a contiguous tertiary carbon center, a quaternary carbon center, and a tertiary alcohol in the

39 crylate, which enables the introduction of a quaternary carbon center.

40 s containing a diaryl-substituted all-carbon quaternary carbon center.

41 n of aldehydes along with the formation of a quaternary carbon center.

42 1,4-dicarbonyl constitution together with a quaternary carbon center.

43 ate a tetracyclic enamide bearing one of the quaternary carbon centers (C7) of the alkaloid, an intra

44 onstructing richly functionalized all-carbon quaternary carbon centers at the beta-position of alipha

45 d be of great potential for the formation of quaternary carbon centers but often give poor yields/con

46 hly substituted cyclobutenes with contiguous quaternary carbon centers can be synthesized easily and

47 This approach to the synthesis of all-carbon quaternary carbon centers does not suffer from isomeriza

48 nown, their application in the generation of quaternary carbon centers in carbocyclic ring systems is

49 tion of hydroformylation to the synthesis of quaternary carbon centers is reported.

50 strategy for installation of the two vicinal quaternary carbon centers of the communesins is reported

51 required stereochemistry of the two adjacent quaternary carbon centers present in mersicarpine.

52 Using a Rh(I)/DPPF system, tertiary and quaternary carbon centers were formed with exclusively b

53 Michael acceptors was developed to introduce quaternary carbon centers with high regio- and diastereo

54 tially valuable tool for the construction of quaternary carbon centers.

55 for altered reactivity and the formation of quaternary carbon centers.

56 transformations forming tetrasubstituted and quaternary carbon centers.

57 a-heptadienes to afford cyclohexenes bearing quaternary carbon centers.

58 nct [4.2.1]-bicyclic skeleton containing two quaternary carbon centers.

59 azlactones containing adjacent tertiary and quaternary carbon centers.

60 s containing alpha-tertiary as well as alpha-quaternary carbon centers.

61 ubstrates containing alpha-tertiary or alpha-quaternary carbon centers.

62 ve configuration of spiroepoxides or related quaternary carbon-containing oxiranes can be troublesome

63 Observation of quaternary carbon epimerization via a retro-Mannich/Mann

64 enient method for the direct construction of quaternary carbons from tertiary alcohols by visible-lig

65 tion of the polymer backbone in alkaline via quaternary carbon hydrolysis and ether hydrolysis, leadi

66 igh yields under mild conditions to form the quaternary carbon in alpha,alpha-disubstituted oxindoles

67 barbituric acid derivatives with an in-ring quaternary carbon in unprecedented enantioselectivity, o

68 three new stereocenters and three continuous quaternary carbons in a single operation in high yield w

69 d densely substituted tropanes incorporating quaternary carbons in good yields and with high regio- a

70 ss beta,gamma-unsaturated ketones containing quaternary carbons in the alpha-position.

71 anocatalysis, the construction of asymmetric quaternary carbons is regarded as a challenging problem

72 hnson-Claisen rearrangement that generates a quaternary carbon next to a glucal-like oxygen.

73 th the known absolute stereochemistry at the quaternary carbon of spiciferone A, spicifernin, and ber

74 The preparation of the two epimers at the quaternary carbon of the 6-deoxy-C-altrose moiety in the

75 n, and nucleophilic addition constructs both quaternary carbons of the cyclooctane and four of the fi

76 ansfer and inverse gated decoupling suppress quaternary-carbon resonances, and T(1)-filtering reduces

77 eta-lactones and beta-lactones bearing alpha-quaternary carbons, respectively.

78 addition of a methyl group to generate a C-3 quaternary carbon resulted in acetamide 6, which showed

79 oxygenated fragments to form the critical C8 quaternary carbon stereocenter and set the stage for ela

80 functionalized beta-ketoesters containing a quaternary carbon stereocenter are obtained with up to 9

81 e fragments are coupled, and the critical C9-quaternary carbon stereocenter formed stereoselectively,

82 taining a hydroxyl substituent adjacent to a quaternary carbon stereocenter in the pyrrolidine ring.

83 taining a hydroxyl substituent adjacent to a quaternary carbon stereocenter is reported.

84 omplex target structure is disconnected at a quaternary carbon stereocenter to fragments of comparabl

85 tionalized branched cyanoesters containing a quaternary carbon stereocenter with a vicinal tertiary s

86 ulfonyliminium ion cyclization to set the C3 quaternary carbon stereocenter, and assemble the diazatr

87 rings and four stereocenters, including one quaternary carbon stereocenter, has been developed.

88 ddition reaction that also generated the C11 quaternary carbon stereocenter.

89 nophosphonates and to phosphonates bearing a quaternary carbon stereocenter.

90 The resultant quaternary carbon stereocenters are formed in high enant

91 tive methods for the construction of acyclic quaternary carbon stereocenters from achiral or chiral r

92 numerous asymmetric methods for formation of quaternary carbon stereocenters in cyclic systems have b

93 ubstituted hydroxylamines, the generation of quaternary carbon stereocenters through carbon-carbon co

94 been documented, the construction of acyclic quaternary carbon stereocenters with control of absolute

95 ketones to the enantioselective synthesis of quaternary carbon stereocenters would be highly valuable

96 Emphasis has been put on methods to create quaternary carbon stereocenters, including syntheses of

97 olecular frameworks containing newly created quaternary carbon stereocenters.

98 ivatives bearing one or multiple tertiary or quaternary carbon stereocenters.

99 ntio- and diastereoselective construction of quaternary carbon stereocenters.

100 tep constructions of molecules with multiple quaternary carbon stereocentres are rare.

101 Quaternary carbon stereocentres-carbon atoms to which fo

102 over four stereocentres, three of which are quaternary carbon stereocentres.

103 reagents and afford 1,4-dienes containing a quaternary carbon stereogenic center at their C-3 site,

104 generation of two new C-C bonds and one new quaternary carbon stereogenic center in a single synthet

105 d bicyclic amides that bear an N-substituted quaternary carbon stereogenic center.

106 d acyclic compounds bearing an N-substituted quaternary carbon stereogenic center.

107 novel approach for the synthesis of acyclic quaternary carbon stereogenic centers and it represents

108 new approach toward the synthesis of acyclic quaternary carbon stereogenic centers and provides the f

109 nerate products containing boron-substituted quaternary carbon stereogenic centers are disclosed.

110 lboronates bearing B-substituted tertiary or quaternary carbon stereogenic centers are presented.

111 responding trisubstituted alkenes, affording quaternary carbon stereogenic centers.

112 -2,8-dioxabicyclo[3.3.0]octanones containing quaternary carbon substituents at C6 is disclosed.

113 Moreover, the introduction of a quaternary carbon was achieved by alkylation with ethyl

114 ss of highly strained molecules possessing a quaternary carbon with bonds that deviate from the canon

115 le to undergo nucleophilic ring opening at a quaternary carbon with complete inversion of the configu