ライフサイエンスコーパス: ring expansion

1 istically interesting products (e.g., double ring expansion).

2 t with both radical rearrangement and cation ring expansion.

3 er, affect the overall barrier to reversible ring expansion.

4 to the ketone followed by rearrangement and ring expansion.

5 cyclopropyl gold(I) carbenes, followed by a ring expansion.

6 ng groups, and provides a method for n-->n+4 ring expansion.

7 trogen ylide formation followed by azetidine ring expansion.

8 o the formal 6-endo products via homoallylic ring expansion.

9 (I)-templated helical knot precursor through ring expansion.

10 igration, similar to that in a Dowd-Beckwith ring expansion.

11 rearrange into cyclohexyne (with DeltaE for ring expansion=-15.1 kcal mol(-1) ).

12 rearrange into cyclopentyne (with DeltaE for ring expansion=-6.2 kcal mol(-1) ).

13 on yields cyclopropylidenecyclobutane, while ring-expansion affords bicyclo[3.2.0]hept-1(5)-ene.

14 y whereas actin reorganizes through cortical ring expansion and clearance from the poles.

15 unusual reactions, including ring couplings, ring expansion and contraction, and fusion of substrates

16 e, is proposed to form and partition between ring expansion and direct fragmentation to alkene; event

17 egioselective, and convergent method for the ring expansion and rearrangement of 1-sulfonyl-1,2,3-tri

18 Ring expansion and ring fragmentation products were synt

19 lowed by an intermolecular reaction during a ring-expansion and a ring-extrusion reaction followed by

20 (6) core bridging, (7) ring contraction, (8) ring expansion, and (9) C-H and C-C bond activation.

21 ric epoxidation of benzylidenecyclopropanes, ring expansion, and Baeyer-Villiger oxidation.

22 A "ring expansion-annulation strategy" for the synthesis of

23 d with our experimental measurements of swim ring expansion as a function of time, demonstrating good

24 plausible mechanism of tetrahydropyrimidine ring expansion based on DFT calculation at B3LYP/6-31+G(

25 They do not undergo ring expansion but form basic nitrenes that protonate to

26 s (F and Cl) raise the activation barrier to ring expansion by approximately 5 kcal/mol.

27 nate carbodiimide, and the scarcely observed ring expansion by insertion of a chloro(imino)phosphine

28 contraction within the carbene prevails over ring-expansion by a factor of 6.7:1.

29 ing some epoxides that do not undergo simple ring-expansion carbonylation.

30 iates into pyrrolizidines through an unusual ring expansion/contraction mechanism, and catalyze the b

31 The observed ring expansion/contraction reactions are characteristic

32 Competition between direct atom transfer and ring expansion followed by diolate cycloreversion is dem

33 A Pd(II)/Bronsted acid catalyzed migratory ring expansion for the synthesis of indene derivatives p

34 , 1-adamantyl, or 3-homoadamantyl, or by the ring expansion-fragmentation of R'CH(2)OCCl, with R' = 1

35 ion pairs, produced by either the direct or ring expansion-fragmentations, were identical, solvent-

36 concept of thionium ion-initiated pinacolic ring expansion has been developed for accessing C4'-spir

37 ite can control whether the enzyme catalyzes ring-expansion, hydroxylation, or both reactions.

38 referred over an allylic pathway wherein the ring expansion in a Pd-pi-allyl intermediate occurs subs

39 stereoelectronic restrictions on homoallylic ring expansion in alkyne reactions and to develop a new

40 owed by reports on the use of cyclic ketones ring expansion in total synthesis.

41 In contrast, ring expansion is observed to be the major reaction path

42 first catalyst to polymerize norbornene via ring expansion metathesis polymerization to yield highly

43 Ring-expansion metathesis polymerization (REMP) mediated

44 lar architecture were developed by combining ring-expansion metathesis polymerization and click chemi

45 lic organic nanostructures were prepared via ring-expansion metathesis polymerization of a dendronize

46 Here, ring-expansion metathesis polymerization was used to syn

47 ocycles were prepared in one step by a novel ring-expansion method using olefin metathesis.

48 ell phenylnitrene, which is known to undergo ring expansion much more readily than phenylcarbene.

49 th anomerization and furanosyl --> pyranosyl ring expansion occurred.

50 The asymmetric gold(I)-catalyzed ring expansion of 1-allenylcyclopropanols is described.

51 We observed ring expansion of 1-methylcyclobutylfluorocarbene at 8 k

52 b) to 1-aza-1,2,4,6-cycloheptatetraene (3b), ring expansion of 1c to 3c is computed to be quite endot

53 obenzoazepinediones 15a-15c via the proposed ring expansion of 3-vinyl-3-hydroxyisoindolinone interme

54 tom tunneling reaction involving spontaneous ring expansion of a fused-ring benzazirine into a seven-

55 A novel, dual-pathway ring expansion of alkynylcyclopropanols is described.

56 rmediate by hydropalladation of allenes, the ring expansion of allenylcyclobutanol substrates proceed

57 tereochemistry, diastereoselective oxidative ring expansion of an alpha-hydroxyfuran to access the py

58 of (+)-plectosphaeroic acid C was formed by ring expansion of an epidisulfide precursor.

59 rst examples where both cyclopropanation and ring expansion of arenes were rendered reversible.

60 The synthesis relied on the B-ring expansion of available 6-keto estradiol derivatives

61 Base-catalyzed ring expansion of both (+/-)/(-)-epi-claulansine D and (

62 The scope and limitations of the ring expansion of cyclic 2-hydroxymethyl amines induced

63 Wacker-type pathway (involving a semipinacol ring expansion of cyclobutanol followed by a reductive e

64 tenones were synthesized by the diazomethane ring expansion of cyclobutanones, produced by the photoc

65 ich included cyclization, rearrangement, and ring expansion of hemiacetal, 15, is proposed.

66 thoxybenzaldehyde demonstrate the reversible ring expansion of methoxyphenylcarbene (CH(3)O-C(6)H(4)-

67 he rate constant for carbon tunneling in the ring expansion of noradamantylmethylcarbene (1d) to 2-me

68 in N, did not play a significant role in the ring expansion of penicillin G by resting cells or cell-

69 n C synthase (DAOCS) catalyses the oxidative ring expansion of penicillin N, the committed step in th

70 Unlike the comparable ring expansion of the (1)A(2) state of phenylnitrene (1b

71 to investigate the potential surface for the ring expansion of the (1)A(2) state of phenylphosphinide

72 analogue was found to undergo an unexpected ring expansion of the bryolactone core to generate the c

73 ermediate with "6-6-5" rings followed by the ring expansion of the C-ring concomitant with the format

74 ction, the reactions involving oxidation and ring expansion of the corrole macrocycle are described c

75 ed by acidic alumina-mediated regioselective ring expansion of the cyclopropyl ketone.

76 the syn-Tp'Re(O)(diolate) complex, formed by ring expansion of the epoxide.

77 pathway, the alkylidene ligand is lost, via ring expansion of the metallacyclobutane intermediate, l

78 do-1-benzyl-beta-lactams, and TEMPO-mediated ring expansion of these compounds to the corresponding N

79 onal theory computations of the Cu-catalyzed ring expansion of vinyloxiranes is mediated by a tracele

80 his paper highlights various methods for the ring expansion of vinyloxiranes, -thiiranes, and -azirid

81 The regiochemistry of ring expansions of 2-substituted cyclic ketones using 1,

82 ction surfaces leading to rearrangements and ring expansions of azapentalene cycloadducts of imidazol

83 es described include EtMgBr-promoted pinacol ring expansions of hydroxy mesylates 23 and 34, intramol

84 prepared under mild conditions by employing ring expansions of silylated methyleneaziridines.

85 he Schmidt reaction permits stereocontrol in ring expansions of symmetrical cyclohexanones.

86 mer: conformational restriction of the sugar ring, expansion of the pyrimidine pi-stacking surface an

87 alosporin C, whereas the W82A mutant reduced ring-expansion of penicillin G (an "unnatural" substrate

88 5L/M306I triple mutant selectively catalyzed ring-expansion of penicillin G and had improved kinetic

89 CS to residue 310 (Delta310 mutant) enhanced ring-expansion of penicillin G by approximately 2-fold.

90 catalyzes two oxidative reactions, oxidative ring-expansion of penicillin N to deacetoxycephalosporin

91 The crucial step in this transformation is a ring-expansion of the anionic intermediate by [1,3] sigm

92 azide addition to the carbonyl, followed by ring expansion or rearrangement, respectively.

93 ces clavuligerus, which selectively catalyze ring-expansion or hydroxylation reactions, respectively.

94 catalysis and gold catalysis is applied to a ring expansion-oxidative arylation reaction.

95 The ring-expansion pathway is described by the rate equation

96 A novel, one-pot ring-expansion procedure was developed using Me3S(O)I, N

97 ey finding is that the five- to six-membered ring expansion process is not a viable reaction pathway

98 ition metal complexes as a catalyst for this ring-expansion process.

99 e to stable structures, can compete with the ring-expansion process.

100 e-like centers that compete effectively with ring expansion processes of cyclopropylcarbenes.

101 H(5))C(triple bond)CTol] (12-E and 12-Z); no ring expansion product was observed.

102 ienone led to the formation of a 2-tropolone ring expansion product, consistent with a direct 1,2-alk

103 te is the ketenimine or a ketenimine-derived ring expansion product.

104 A ring-expansion product derived from the norcaranyl C-2 c

105 oducts, while the O-atom found in the cation ring-expansion products was predominantly obtained by re

106 in Wagner-Meerwein shifts was examined in a ring expansion protocol.

107 ynthesis are a silicate-directed elimination/ring expansion reaction and a highly diastereoselective

108 The ring expansion reaction led to a variety of functionaliz

109 pin-2-ones based on the nucleophile-mediated ring expansion reaction of 5-functionalized 4-mesyloxyme

110 of Pd(II)-Bronsted acid catalyzed migratory ring expansion reaction of an indenyl cyclobutanol to a

111 sis of 1 and 2 required the development of a ring expansion reaction to provide a 6-membered ring sui

112 ch also required the development of a unique ring expansion reaction to provide a six-membered ring s

113 to form the bicyclic intermediate 2c in the ring expansion reaction, is computed to be only slightly

114 xample of a phosphorus analog of the Buchner ring expansion reaction.

115 tically active 3-substituted piperidines via ring expansion reaction.

116 t, Delta310/M306I, selectively catalyzed the ring-expansion reaction and had similar kinetic paramete

117 l provides an unusual opportunity to study a ring-expansion reaction controlled entirely by stereoele

118 The technique described here involves a ring-expansion reaction of a 4-substituted cyclohexanone

119 It was also found that the ring-expansion reaction rate is more than 1 order of mag

120 The ring-expansion reaction takes place at 10 K with a rate

121 nine, but could be explained by a subsequent ring-expansion reaction to give an eight-membered ring v

122 protocol carries out the diastereoselective ring-expansion reaction with higher selectivity than com

123 The origins of these differences between the ring expansion reactions of 1b and 1c have been elucidat

124 Ring expansion reactions of strained vinylic heterocycli

125 es of arenes in thermally reversible Buchner ring expansion reactions, marking the first examples whe

126 s of oxetane derivatives in ring-opening and ring-expansion reactions are described.

127 ne) species by tetrabromodiborane(4)-induced ring-expansion reactions of cobaltocene.

128 n heterocycles can be prepared by performing ring-expansion reactions of gamma-silyloxy-gamma-lactams

129 hlorins is also susceptible to oxidation and ring-expansion reactions, generating chromene-annulated

130 These include ring expansion, ring opening, and C-2 functionalization.

131 6',7',1'-lmnop]chrysene (14) by a double 5/6 ring-expansion/ring-contraction.

132 photoproduct proceeds more rapidly than the ring-expansion route.

133 xycyclization (spirocyclic selenolactams) or ring expansion (selenoquinolones) can be achieved throug

134 chanistic evidence for the 5-exo cyclization/ring expansion sequence.

135 be generated through a telescoped acylation/ring-expansion sequence, leading to the insertion of lin

136 iketene annulation reaction and an oxidative ring expansion strategy designed to complement the presu

137 own" from smaller rings using the successive ring-expansion (SuRE) method.

138 kers were made by regiochemically controlled ring expansion techniques (for substitution on Aca posit

139 esulted in the investigation of sulfur ylide ring expansions, thiocarbonyl chemistry, azomethine ylid

140 nes, and their homologues) undergo migratory ring expansion through deprotonation of their benzylic u

141 ethoxycyclopropyl-d3-methylcarbene undergoes ring expansion to 1-d3-methylcyclobutene.

142 ene has been found experimentally to undergo ring expansion to 2-chloroadamantene at cryogenic temper

143 arting from 1-isoquinolylcarbene; path a via ring expansion to 3-aza-benzo[c]cyclohepta-1,2,4,6-tetra

144 nother portion of 2-pyridylcarbene undergoes ring expansion to 4-azacyclohepta-1,2,4,6-tetraene 42, w

145 flates and subsequently treated with base, a ring expansion to 6,7,8,13-tetrahydro-5H-dibenzo[c,f]azo

146 id, which when heated in ethanol underwent a ring expansion to a hydroximino derivative, 38, of compo

147 cis to the ester group was found to undergo ring expansion to a mixture of cis- and trans-oxazolidin

148 c palladium intermediate, (3) regioselective ring expansion to a palladacycle, and (4) reductive elim

149 condensations, Diels-Alder chemistry, and a ring expansion to advance a chiral starting material con

150 owed by homoallyl (3-exo-trig/fragmentation) ring expansion to afford the benzylic radical necessary

151 ycloaddition, a Claisen rearrangement, and a ring expansion to construct the core of the frondosin A

152 pene cyclase with a subsequent Ths-dependent ring expansion to form tetrahymanol.

153 ion to the aromatic ring occurs, followed by ring expansion to generate novel bicyclic sulfones.

154 the alkenyl cyclopropane 2 underwent smooth ring expansion to give the sesquiterpene (-)-delobabone

155 e 36, which undergoes tandem azide reduction/ring expansion to macrolactam 37.

156 carbene rearrangement, whereby DPC undergoes ring expansion to phenylcycloheptatetraene (PhCHT) follo

157 e, isamic acid 1, led to decarboxylation and ring expansion to quinazolino[4,5-b]quinazoline-6,8-dion

158 C-H activation with concomitant semipinacol ring expansion to the nascent pi-allylpalladium species.

159 nt dioxygenase which catalyzes the oxidative ring expansion to the tropolone nucleus via hydroxylatio

160 thylene aziridines results in a formal [3+1] ring expansion to yield highly substituted methylene aze

161 uivalents of alkynes by coupling homoallylic ring expansion to yield the formal "6-endo" products wit

162 e moiety were able to undergo regioselective ring expansions to produce corresponding cyclopentanones

163 These compounds undergo facial oxy-Cope ring expansions upon treatment with vinyllithium; the fo

164 ivity was also observed in the carbonylative ring expansion using Co(2)(CO)(8) to give a beta-lactam.

165 e five-membered ring in advance of transient ring expansion via diketone formation and intramolecular

166 of bishomoallylic amines followed by in situ ring-expansion (via intramolecular ring-opening of the c

167 ditions were used with 14 other penicillins, ring expansion was achieved in all cases.

168 bined with a subsequent cobalt(II)-catalyzed ring expansion with 1,3-diketones.

169 eterocycles, cyclopropanation and subsequent ring expansions, ylide formation with subsequent rearran