1006-26-4Relevant academic research and scientific papers
Dipyrrolylnaphthyridine-based Schiff-base cryptands and their selective gas adsorption properties
Wang, Fei,Sikma, Eric,Duan, Zhiming,Lei, Chuanhu,Zhang, Zhan,Humphrey, Simon M.,Sessler, Jonathan L.
, p. 424 - 431 (2020)
Presented here is the synthesis of three new Schiff-base cryptands, 4-6. Dynamic covalent imine bond formation via the condensation of a dialdehyde (7 or 8) with two different tris-amines allowed for the preparation of 4-6 in 84%, 80% and 83% yield, respectively. These systems were characterized by NMR spectroscopy, mass spectra, and, in the case of 5, single crystal X-ray diffraction analysis. These cages act as selective CO2 gas adsorbing materials in the solid state.
β-Octamethoxy-Substituted 22π and 26π Stretched Porphycenes: Synthesis, Characterization, Photodynamics, and Nonlinear Optical Studies
Rana, Anup,Lee, Sangsu,Kim, Dongho,Panda, Pradeepta K.
, p. 12129 - 12135 (2015)
Three meso-expanded tetrapyrrolic aromatic macrocycles, including 22π and 26π acetylene-cumulene bridged stretched octamethoxyporphycenes and octamethoxy[22]porphyrin-(2.2.2.2), are reported, for the first time, by modification of previously reported synthetic methods. This strategy led to an enhancement in the overall yield of their corresponding octaethyl analogues. The methoxy-substituted expanded porphycenes display slightly blueshifted absorption relative to their ethyl analogues, along with very weak fluorescence, probably due to efficient intramolecular charge transfer (ICT). Additionally, the two-photon absorption (TPA) cross sections of these macrocycles were evaluated; these are strongly related to core expansion of the porphyrin aromaticity through increased meso-bridging carbon atoms as well as conformational flexibility and substitution effects at the macrocyclic periphery. In particular, the octamethoxy stretched porphycenes display strong TPA compared with the octaethyl analogues due to the dominant ICT character of methoxy groups with a maximum TPA cross section of 830 GM at 1700 nm observed for 26π-octamethoxyacetylene-cumuleneporphycene.
An artificial receptor for dimethyl aspartate
Mizutani, Tadashi,Murakami, Takeshi,Kurahashi, Takuya,Ogoshi, Hisanobu
, p. 539 - 548 (1996)
[trans-5,15-Bis(2,7-dihydroxy-1-naphthyl)-2,3,7,8,12,13,17,18-octaethy lporphyrinato]zinc(II) (1), a trifunctionalized porphyrin host, was prepared as a receptor for amino acid derivatives, particularly those having a hydrogen-bonding site in the side chain. The free energy changes for the binding of Leu-OMe, Asp-OMe, and Glu-OMe to 1 were -5.8 kcal/mol, -6.6 kcal/mol, and -5.9 kcal/mol, showing a selectivity for Asp-OMe. 1H NMR titration experiments indicated that three simulteneous attractive interactions, one coordination interaction, and two hydrogen-bonding interactions, are operating in the host-guest complex. The preference for Asp-OMe over Glu-OMe was found to originate from the favorable enthalpy term for Asp-OMe. The free energy change, the enthalpy change, and the entropy change were determined and split into contributions arising from coordination interaction and from hydrogen-bonding interactions by use of reference hosts. Comparison of enthalpy and entropy changes suggests that the host-guest complex becomes more ordered as the number of recognition pairs increases.
Octaethyl-21H,24H-bilin-1,19-dione (Octaethylbilatriene-abc)
Bonnett, Raymond,Buckley, Dennis G.,Hamzetash, Dariush
, p. 322 - 325 (1981)
A synthesis of the octaethylbilindione (1) from 3,4-diethylpyrrole is described which is suitable for the preparation of this valuable model compound in quantity.
Meso-unsubstituted iron corrole in hemoproteins: Remarkable differences in effects on peroxidase activities between myoglobin and horseradish peroxidase
Matsuo, Takashi,Hayashi, Akihiro,Abe, Masato,Matsuda, Takaaki,Hisaeda, Yoshio,Hayashi, Takashi
, p. 15124 - 15125 (2009)
(Figure Presented) Myoglobin (Mb) and horseradish peroxidase (HRP) were both reconstituted with a meso-unsubstituted iron corrole and their electronic configurations and peroxidase activities were investigated. The appearance of the 540 nm band upon incorporation of the iron corrole into apoMb indicates axial coordination by the proximal histidine imidazole in the Mb heme pocket. Based on 1H NMR measurements using the Evans method, the total magnetic susceptibility of the iron corrole reconstituted Mb was evaluated to be S = 3/2. In contrast, although a band does not appear in the vicinity of 540 nm during reconstitution of the iron corrole into the matrix of HRP, a spectrum similar to that of the iron corrole reconstituted Mb is observed upon the addition of dithionite. This observation suggests that the oxidation state of the corrole iron in the reconstituted HRP can be assigned as +4. The catalytic activities of both proteins toward guaiacol oxidation are quite different; the iron corrole reconstituted HRP decelerates H2O2-dependent oxidation of guaiacol, while the same reaction catalyzed by iron corrole reconstituted Mb has the opposite effect and accelerates the reaction. This finding can be attributed to the difference in the oxidation states of the corrole iron when these proteins are in the resting state.
Regioselective substituent effects upon the synthesis of dipyrrins from 2-formyl pyrroles
Beh, Michael H.R.,Figliola, Carlotta,Lund, Kate-Lyn A.R.,Kajetanowicz, Aleksandra K.,Johnsen, Ann E.,Aronitz, Elise M.,Thompson, Alison
supporting information, p. 779 - 784 (2018/07/06)
The synthesis of symmetric α-free meso-H-dipyrrin hydrobromides from 5-H-2-formyl pyrroles was investigated. The self-condensation produces regioisomeric dipyrrins through adoption of two mechanistic pathways. The key difference between the two pathways lies in which position of the pyrrole directs nucleophilic attack. Through a systematic study involving various substituted and (or) isotopically labelled 5-H-2-formyl pyrroles, we herein provide evidence to suggest that not only do two mechanistic pathways exist, but the steric bulk of the substituent adjacent to the 5-unsubstituted position influences which pathway dominates.
Synthesis of 2,2′-bipyrrole-5-carboxaldehydes and their application in the synthesis of B-ring functionalized prodiginines and tambjamines
Kancharla, Papireddy,Reynolds, Kevin A.
, p. 8375 - 8385 (2013/09/02)
Facile, versatile, and cost-effective synthetic routes for the preparation of a range of new 3-alkyl-, 4-alkyl-, 3,4-dialkyl-, and 3-halo-4-alkyl-2, 2′-bipyrrole-5-carboxaldehydes have been developed. These 2,2′-bipyrrole-5-carboxaldehydes offer interesting potential as building blocks for making bioactive natural and unnatural products, as demonstrated by the synthesis of B-ring functionalized prodiginines (PGs) and tambjamines.
Expanded scope of synthetic bacteriochlorins via improved acid catalysis conditions and diverse dihydrodipyrrin-acetals
Krayer, Michael,Ptaszek, Marcin,Kim, Han-Je,Meneely, Kelly R.,Fan, Dazhong,Secor, Kristen,Lindsey, Jonathan S.
experimental part, p. 1016 - 1039 (2010/04/04)
(Chemical Equation Presented) Bacteriochlorins are attractive candidates for a wide variety of photochemical studies owing to their strong absorption in the near-infrared spectral region. The prior acid-catalysis conditions [BF 3 · O(Et)2 in CH3CN at room temperature] for self-condensation of a dihydrodipyrrin-acetal (bearing a geminal dimethyl group in the pyrroline ring) typically afforded a mixture of three macrocycles: the expected 5-methoxybacteriochlorin (MeOBC-type), a 5-unsubstituted bacteriochlorin (HBC-type), and a free base B,D-tetradehydrocorrin (TDC-type). Here, a broad survey of >20 acids identified four promising acid catalysis conditions of which TMSOTf/2,6-di-tert-butylpyridine in CH2Cl 2 at room temperature was most attractive owing to formation of the 5-methoxybacteriochlorin as the sole macrocycle regardless of the pyrrolic substituents in the dihydrodipyrrin-acetal (electron-withdrawing, electron-donating, or no substituent). Eleven new dihydrodipyrrin-acetals were prepared following standard routes. Application of the new acid catalysis conditions has afforded diverse bacteriochlorins (e.g., bearing alkyl/ester, aryl/ester, diester, and no substituents) in a few days from commercially available starting materials. Consideration of the synthetic steps and yields for formation of the dihydrodipyrrin-acetal and bacteriochlorin underpins evaluation of synthetic plans for early installation of bacteriochlorin substituents via the dihydrodipyrrin-acetal versus late installation via derivatization of β-bromobacteriochlorins. Treatment of the 5-methoxybacteriochlorins with NBS gave regioselective 15-bromination when no pyrrolic substituents were present or when each pyrrole contained two substituents; on the other hand, the presence of a β-ethoxycarbonyl group caused loss of regioselectivity. The 15 new bacteriochlorins prepared herein exhibit a long-wavelength absorption band in the range 707-759 nm, providing tunable access to the near-infrared region. Taken together, this study expands the scope of available bacteriochlorins for fundamental studies and diverse applications. 2010 American Chemical Society.
Non-symmetric tripyrranes in the synthesis of novel macrocycles
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Page 23, (2010/11/30)
The present invention provides certain non-symmetric tripyrranes; that is, tripyrranes that do not contain a mirror plane of symmetry perpendicular to the plane containing the tripyrrane. Further, the invention includes texaphyrin compounds and sapphyrin
