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Jacquelyn A. Carioscia Lauren Schneidewind Casey O'Brien Robert Ely Caitlin Feeser Neil Cramer Christopher N. Bowman 《Journal of polymer science. Part A, Polymer chemistry》2007,45(23):5686-5696
The ability to prepare high Tg low shrinkage thiol–ene materials is attractive for applications such as coatings and dental restoratives. However, thiol and nonacrylated vinyl materials typically consist of a flexible backbone, limiting the utility of these polymers. Hence, it is of importance to synthesize and investigate thiol and vinyl materials of varying backbone chemistry and stiffness. Here, we investigate the effect of backbone chemistry and functionality of norbornene resins on polymerization kinetics and glass transition temperature (Tg) for several thiol–norbornene materials. Results indicate that Tgs as high as 94 °C are achievable in thiol–norbornene resins of appropriately controlled chemistry. Furthermore, both the backbone chemistry and the norbornene moiety are important factors in the development of high Tg materials. In particular, as much as a 70 °C increase in Tg was observed in a norbornene–thiol specimen when compared with a sample prepared using allyl ether monomer of analogous backbone chemistry. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5686–5696, 2007 相似文献
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Dr. Subhabrata Chaudhury Dr. Penchala Narasimharao Meka Dr. Monimoy Banerjee Caitlin N. Kent Prof. Dr. Brian S. J. Blagg 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(59):14747-14764
The 90 kDa heat shock proteins (Hsp90) are molecular chaperones that are responsible for the folding and/or trafficking of ∼400 client proteins, many of which are directly associated with cancer progression. Consequently, inhibition of Hsp90 can exhibit similar activity as combination therapy as multiple signaling nodes can be targeted simultaneously. In fact, seventeen small-molecule inhibitors that bind the Hsp90 N-terminus entered clinical trials for the treatment of cancer, all of which exhibited pan-inhibitory activity against all four Hsp90 isoforms. Unfortunately, most demonstrated undesired effects alongside induction of the pro-survival heat shock response. As a result, isoform-selective inhibitors have been sought to overcome these detriments. Described herein is a structure-based approach to design Hsp90β-selective inhibitors along with preliminary SAR. In the end, compound 5 was shown to manifest ∼370-fold selectivity for Hsp90β versus Hsp90α, and induced the degradation of select Hsp90β-dependent clients. These data support the development of Hsp90β-selective inhibitors as a new paradigm to overcome the detriments associated with pan-inhibition of Hsp90. 相似文献
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Caitlin E. Karver Eric S. Molina Erin T. Economos Jonathan C. Fuentes Socrates M. Kaitson Samuel Kogan 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):101-105
Electrophilic trisubstituted ethylenes, halogen ring-substituted methyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO2CH3 (where R is 3-Br-4-CH3O, 5-Br-2-CH3O, 2-F-5-CH3, 2-F-6-CH3, 4-F-3-CH3, 4-F-3-PhO, 2-F-5-I, 2-F-6-I, 2-F3C, 4-F3C) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and methyl cyanoacetate, and characterized by CHN analysis, IR, 1H and 13C-NMR. All the ethylenes were copolymerized with styrene (M1) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 2-F-5-CH3 (6.4) > 4-F-3-PhO (5.6) > 4-F3C (4.8) > 3-Br-4-CH3O (3.7) > 2-F-5-I (3.6) > 2-F3C (2.2) > 2-F-6-I (2.1) > 5-Br-2-CH3O (1.9) > 4-F-3-CH3 (1.8) > 2-F-6-CH3 (1.2). Relatively high T g of the copolymers in comparison with that of polystyrene indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500°C range with residue (2–21% wt), which then decomposed in the 500–800°C range. 相似文献
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Caitlin M. McMahon Prof. Erik J. Alexanian 《Angewandte Chemie (International ed. in English)》2014,53(23):5974-5977
A palladium‐catalyzed, intermolecular Heck‐type coupling of alkyl iodides and alkenes is described. This process is successful with a variety of primary and secondary unactivated alkyl iodides as reaction partners, including those with hydrogen atoms in the β position. The mild catalytic conditions enable intermolecular C? C bond formations with a diverse set of alkyl iodides and alkenes, including substrates containing base‐ or nucleophile‐sensitive functionality. 相似文献
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Molecularly Precise Dendrimer–Drug Conjugates with Tunable Drug Release for Cancer Therapy 下载免费PDF全文
Dr. Zhuxian Zhou Dr. Xinpeng Ma Dr. Caitlin J. Murphy Dr. Erlei Jin Dr. Qihang Sun Prof. Youqing Shen Edward A. Van Kirk Prof. William J. Murdoch 《Angewandte Chemie (International ed. in English)》2014,53(41):10949-10955
The structural preciseness of dendrimers makes them perfect drug delivery carriers, particularly in the form of dendrimer–drug conjugates. Current dendrimer–drug conjugates are synthesized by anchoring drug and functional moieties onto the dendrimer peripheral surface. However, functional groups exhibiting the same reactivity make it impossible to precisely control the number and the position of the functional groups and drug molecules anchored to the dendrimer surface. This structural heterogeneity causes variable pharmacokinetics, preventing such conjugates to be translational. Furthermore, the highly hydrophobic drug molecules anchored on the dendrimer periphery can interact with blood components and alter the pharmacokinetic behavior. To address these problems, we herein report molecularly precise dendrimer–drug conjugates with drug moieties buried inside the dendrimers. Surprisingly, the drug release rates of these conjugates were tailorable by the dendrimer generation, surface chemistry, and acidity. 相似文献
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Kaitlin A. Chambers Nile S. Abularrage Caitlin J. Hill Imran H. Khan Rebecca A. Scheck 《Angewandte Chemie (International ed. in English)》2020,59(19):7350-7355
Bacterial phosphothreonine lyases, or phospholyases, catalyze a unique post‐translational modification that introduces dehydrobutyrine (Dhb) or dehydroalanine (Dha) in place of phosphothreonine or phosphoserine residues, respectively. We report the use of a phospha‐Michael reaction to label proteins and peptides modified with Dha or Dhb. We demonstrate that a nucleophilic phosphine probe is able to modify Dhb‐containing proteins and peptides that were recalcitrant to reaction with thiol or amine nucleophiles under mild aqueous conditions. Furthermore, we used this reaction to detect multiple Dhb‐modified proteins in mammalian cell lysates, including histone H3, a previously unknown target of phospholyases. This method should prove useful for identifying new phospholyase targets, profiling the biomarkers of bacterial infection, and developing enzyme‐mediated strategies for bioorthogonal labeling in living cells. 相似文献
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Caitlin F. Zipp Manuel A. Fernandes Joseph P. Michael Susan Winks 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(11):o553-o554
The title compound, C7H13NO, forms R22(8) N—H...O hydrogen‐bonded dimers and C4 N—H...O‐linked chains, which are further stabilized by a C—H...O interaction. The combination of these interactions results in a hydrogen‐bonded network parallel to (100), with a motif that can be described by the secondary graph set R46(16). The existence of the same hydrogen‐bonding motif in 1‐phenylcyclopentanecarboxamide and 1‐(2‐bromophenyl)cyclohexanecarboxamide [Lemmerer & Michael (2008). CrystEngComm, 10 , 95–102 indicates that replacing the H atom on position 1 with a more bulky group does not necessarily disrupt the observed hydrogen‐bonding pattern. The presence of a C—H...O interaction to stabilize the R46(16) network does, however, seem to be required. In addition, the title compound is isomorphous with a previously published structure of cyclopentanecarboxamide [Winter et al. (1981). Acta Cryst. B 37 , 2183–2185]. 相似文献