Phosphatidylcholines and their analogs, the functional building block of the membrane, are recently found to mediate multiple physiological processes and exhibit a broad range of desirable pharmacological effects, whi...Phosphatidylcholines and their analogs, the functional building block of the membrane, are recently found to mediate multiple physiological processes and exhibit a broad range of desirable pharmacological effects, which involve hydrophobic lipophilic interactions (HLI) between the phospholipid and the cell membrane. The HLI behavior of phosphatidylcholines (Ln) and their analogues 1, 2-diacyI-sn-glycerol-3-phosphoric add bro-moethyl ester (Pn), have been investigated in MeOH-H2O binary systems of different volume fractions (designated as Φ) of the organic component, by employing a-nephthylethyl lauryl ether (Np-12) as fluorescent probe. A very interesting observation is that the Ln possesses double character, i.e., it behaves both as an aggregator and as a deaggregator. The effects of the structure and the environment on the coaggregation and deag-gregation are also discussed.展开更多
Electron-transfer processes facilitated by hydrophobic-lipophilic interaction (HLI) between excited N-alkylcarbazoles (1-n, n = 4, 8, 12, 16) as electron donors and 2,4-dinitrophenyl carboxylates (2-n, n = 4, 8, 12, 1...Electron-transfer processes facilitated by hydrophobic-lipophilic interaction (HLI) between excited N-alkylcarbazoles (1-n, n = 4, 8, 12, 16) as electron donors and 2,4-dinitrophenyl carboxylates (2-n, n = 4, 8, 12, 16) or pentafluorophenyl carboxylates (3-n, n = 4, 8, 12, 16) as electron acceptors have been investigated by means of fluorescence spectroscopy in aqueous or aquiorgano binary mixtures. The fluorescence quenching of -n* by 2-n or - n indicates that preassociation precedes the electron transfer. The extent of HLI-driven coaggregation of the acceptor and the donor may be assessed from the B value of the equation I0/I = A + B [Q]. The chain-length effect and possibly also a chain-fold-ability effect, as well as the solvent aggregating power (SAgP) effect have been observed. Comparison of roe quenching constants (B) for 1-n*/2-n combinations and 1-n*/ 3-n combinations shows that the order of increasing B values for the quenching processes is 3-n < 2-n.展开更多
基金National Natural Science Foundation of China(No.29392201).
文摘Phosphatidylcholines and their analogs, the functional building block of the membrane, are recently found to mediate multiple physiological processes and exhibit a broad range of desirable pharmacological effects, which involve hydrophobic lipophilic interactions (HLI) between the phospholipid and the cell membrane. The HLI behavior of phosphatidylcholines (Ln) and their analogues 1, 2-diacyI-sn-glycerol-3-phosphoric add bro-moethyl ester (Pn), have been investigated in MeOH-H2O binary systems of different volume fractions (designated as Φ) of the organic component, by employing a-nephthylethyl lauryl ether (Np-12) as fluorescent probe. A very interesting observation is that the Ln possesses double character, i.e., it behaves both as an aggregator and as a deaggregator. The effects of the structure and the environment on the coaggregation and deag-gregation are also discussed.
文摘Electron-transfer processes facilitated by hydrophobic-lipophilic interaction (HLI) between excited N-alkylcarbazoles (1-n, n = 4, 8, 12, 16) as electron donors and 2,4-dinitrophenyl carboxylates (2-n, n = 4, 8, 12, 16) or pentafluorophenyl carboxylates (3-n, n = 4, 8, 12, 16) as electron acceptors have been investigated by means of fluorescence spectroscopy in aqueous or aquiorgano binary mixtures. The fluorescence quenching of -n* by 2-n or - n indicates that preassociation precedes the electron transfer. The extent of HLI-driven coaggregation of the acceptor and the donor may be assessed from the B value of the equation I0/I = A + B [Q]. The chain-length effect and possibly also a chain-fold-ability effect, as well as the solvent aggregating power (SAgP) effect have been observed. Comparison of roe quenching constants (B) for 1-n*/2-n combinations and 1-n*/ 3-n combinations shows that the order of increasing B values for the quenching processes is 3-n < 2-n.