25983-52-2Relevant academic research and scientific papers
Synthesis and protein kinase inhibitory activity of balanol analogues with modified benzophenone subunits
Lampe, John W.,Jagdmann Jr., G. Erik,Johnson, Mary George,Lai, Yen-Shi,Lowden, Christopher T.,Lynch, Michael P.,Mendoza, José S.,Murphy, Marcia M.,Wilson, Joseph W.,Ballas, Lawrence M.,Carter, Kiyomi,Biggers, Christopher K.,Darges, James W.,Davis, Jefferson E.,Hubbard, Frederick R.,Stamper, Mark L.,Defauw, Jean M.,Foglesong, Robert J.,Hall, Steven E.,Heerding, Julia M.,Hollinshead, Sean P.,Hu, Hong,Hughes, Philip F.
, p. 2624 - 2643 (2007/10/03)
A series of analogues of the protein kinase C (PKC) inhibitory natural product balanol which bear modified benzophenone subunits are described. The analogues were designed with the goal of uncovering structure -activity features that could be used in the development of PKC inhibitors with a reduced polar character compared to balanol itself. The results of these studies suggest that most of the benzophenone features found in the natural product are important for obtaining potent PKC inhibitory compounds. However, several modifications were found to lead to selective inhibitors of the related enzyme protein kinase A (PKA), and several specific modifications to the polar structural elements of the benzophenone were found to provide potent PKC inhibitors. In particular, it was found that replacement of the benzophenone carboxylate with bioisosteric equivalents could lead to potent analogues. Further, a tolerance for lipophilic substituents on the terminal benzophenone ring was uncovered. These results are discussed in light of recently available structural information for PKA.
Enantiopure dendrimers derived from the 1,1'-binaphthyl moiety: A correlation between chiroptical properties and conformation of the 1,1'- binaphthyl template
Rosini, Carlo,Superchi, Stefano,Peerlings,Meijer
, p. 61 - 71 (2007/10/03)
The absorption and CD spectra of a series of Frechet (compounds 7-10) and backfolding (compounds 11-12) dendrimers derived from enantiopure (S)- 2,2'-dihydroxy-1,1'-binaphthalene have been recorded (THF) in the range 200- 350 nm. All the compounds examined show a positive couplet between 200 and 240 nm (1B transition of the 2-naphthol chromophore), the intensity of which (Δε(max) of the low-energy branch) ranges between 100 and 40. By means of the DeVoe polarizability model the intensity of the 1B couplet has been calculated vs. the dihedral angle θ. This analysis provides θ angles of 95- 110° for the Frechet dendrimers and 100-110°for the backfolding compounds. These values clearly indicate that the torsional angle θ, defined by the two naphthalene planes, never exceeds the critical value of 110°. This investigation confirms the wide utility of CD spectroscopy to provide geometrical information that cannot be obtained by other types of structural analysis.
Chiral dendrimers with backfolding wedges
Peerlings,Trimbach,Meijer
, p. 497 - 498 (2007/10/03)
Dendritic wedges with a substitution pattern that forces the growth inwards are introduced and the use of this new building strategy is exemplified in the synthesis and chiroptical properties of a chiral dendrimer.
Synthesis of porphyrins tailored with eight facially-encumbering groups. An approach to solid-state light-harvesting complexes
Wagner,Wagner, Richard W.,Lindsey,Lindsey, Jonathan S.,Turowska-Tyrk,Turowska-Tyrk, Ilona,Scheidt,Scheidt, W. Robert
, p. 11097 - 11112 (2007/10/02)
Synthetic models of the photosynthetic antenna complexes must achieve long-range 3-dimensional order encompassing a large number of porphyrinic pigments with limited direct contact of the pigments. In order to develop solid-state antenna complexes, we have synthesized porphyrins bearing benzyloxy groups projecting over both faces and optionally also around the periphery of the porphyrin. Routes have been established for prefunctionalizing benzaldehydes with various benzyloxy groups. Reaction of 2,6-bis, 3,5-bis, or 2,4,6-tris(benzyloxy)benzaldehydes with pyrrole via the room temperature two-step one-flask porphyrin reaction provides direct access to the facially-encumbered porphyrins. The benzyloxybenzaldehydes react as efficiently as methoxybenzaldehydes, indicating the utility of the -OCH2- unit for introducing large substituents near the face of the porphyrin. The octakis and dodecakis(benzyloxy)porphyrins exhibit characteristic porphyrin absorption and fluorescence properties in solution. The crystal structure of meso-tetrakis[2,6-bis(2,3,4,5,6-pentalfuorobenzyloxy)phenyl]porphyrin has been determined. The pentafluorobenzyloxy substituents provide a cavity on each side of the porphyrin plane which has an approximate cylindrical shape with a diameter of ~7.5 A and a height of ≥4.5 A. The porphyrin core parameters are those obtained for free base derivatives in which the inner hydrogen atoms are ordered. Crystal data: a=14.759 (1) A, b=25.519 (2) A, c=13.100 (1) A, α=100.04 (1), β=99.83 (1), γ=88.25 (1), V=4767.3 (6) A3, all measurements at 127 K, triclinic, space group P1, Z=2 R1(F)=0.097, for 10020 'observed' data, and wR2(F2)=0.275 for 17761 total unique (all) data.
Synthesis and Fluorescence Properties of Selectively Metallated Diporphyrins with Electron-Accepting Moieties
Nagata, Toshi
, p. 3005 - 3016 (2007/10/02)
Synthesis of selectively metallated diporphyrins with electron-accepting moieties is described.Steady-state fluorescence spectra of these compounds showed substantial quenching of the fluorescence of the free-base porphyrin.A possible "superexchange" mechanism of long-range electron transfer is discussed.
