NMR-based molecular ruler for determining the depth of intercalants within the lipid bilayer
摘要:
The development of "molecular rulers" would allow one to quantitatively locate intercalants within the liposomal bilayer. To this end, we have attempted to correlate the C-13 NMR chemical shift of a polarizable "reporter" carbon (e.g., carbonyl) of the intercalant-with the E-T(30) polarity it experiences, and with its Angstrom distance from the interface. This requires families of molecules with the same two "reporter carbons" separated by a fixed distance, residing at various depths/polarities within the bilayer. The families studied included 4,4-dialkylcyclohexa-2,5-dienones 1, benzenediacetic esters 15, benzenedipropionic esters 17, 4-alkoxybenzaldehydes 19 and methyl 4-alkoxybenzoates 22. These compounds possessed the following characteristics: (1) a planar backbone; (2) polar/hydrophilic "head" groups: (3) modular hydrophobic tails; (4) large changes in the C-13 NMR chemical shift (Delta delta) of the reporter atoms with sol- vent polarity. These studies revealed a fifth requirement, namely: (5) the reporter carbons must not be strongly conjugated, lest it reflect the charge build-up at another site within the conjugated system. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
NMR-based molecular ruler for determining the depth of intercalants within the lipid bilayer
摘要:
The development of "molecular rulers" would allow one to quantitatively locate intercalants within the liposomal bilayer. To this end, we have attempted to correlate the C-13 NMR chemical shift of a polarizable "reporter" carbon (e.g., carbonyl) of the intercalant-with the E-T(30) polarity it experiences, and with its Angstrom distance from the interface. This requires families of molecules with the same two "reporter carbons" separated by a fixed distance, residing at various depths/polarities within the bilayer. The families studied included 4,4-dialkylcyclohexa-2,5-dienones 1, benzenediacetic esters 15, benzenedipropionic esters 17, 4-alkoxybenzaldehydes 19 and methyl 4-alkoxybenzoates 22. These compounds possessed the following characteristics: (1) a planar backbone; (2) polar/hydrophilic "head" groups: (3) modular hydrophobic tails; (4) large changes in the C-13 NMR chemical shift (Delta delta) of the reporter atoms with sol- vent polarity. These studies revealed a fifth requirement, namely: (5) the reporter carbons must not be strongly conjugated, lest it reflect the charge build-up at another site within the conjugated system. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
The application of cyclic and acyclic enol ethers as electrophiles in cross coupling reactions offers new possibilities for the preparation of functional compounds.
环状和非环状烯醇醚作为亲电试剂在交叉偶联反应中的应用为功能化合物的制备提供了新的可能性。
Synthesis and Notable Antimalarial Activity of Acyclic Peroxides, 1-(Alkyldioxy)-1-(methyldioxy)cyclododecanes
Of several bis(alkyldioxy)alkanes and the related acyclic peroxides prepared in this study, 1,1-bis(methyldioxy)cyclododecane showed the most notable antimalarial activity particularly in vivo (almost a half of that of artemisinin).
Intramolecular carbon-hydrogen insertions of alkylidenecarbenes. I. Selectivity
作者:John C. Gilbert、David H. Giamalva、Upali Weerasooriya
DOI:10.1021/jo00174a019
日期:1983.12
Generation of aldehydic enol ethers and enamines by olefination of ketones
作者:John C. Gilbert、Upali Weerasooriya
DOI:10.1021/jo00152a008
日期:1983.2
Reaction of Phenylselenenyl Chloride with Enol Ethers and 1,2-Ethanediyl Acetals. Synthesis of α-Phenylseleno-aldehydes and α-Phenylseleno-acetals