Aggregation forms of 8-Ethyl-12-Ethyl Farneshyl bacteriochlorophyll c in methanol-chloroform mixtures as revealed by 1H NMR spectroscopy
| Main Authors: | Tadashi, Mizoguchi, Leenawaty, Limantara, Katsumi, Matsuura, Keizo, Shimada, Yasushi, Koyama |
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| Format: | Article PeerReviewed |
| Terbitan: |
, 1996
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| Subjects: | |
| Online Access: |
http://eprints.upj.ac.id/id/eprint/73/ https://www.sciencedirect.com/science/article/abs/pii/0022286095092005 |
Daftar Isi:
- 8-Ethyl-12-ethyl farnesyl bacteriochlorophyll c was dissolved in chloroform and changes in the 1H NMR spectrum due to the titration of methanol were traced. Based on the changes in chemical shift and in peak intensity, the structures of two aggregate forms have been proposed. Form I showing the Qy electron absorption at 675 nm was ascribed to a dimer which has a “piggy-back” stacking of the macrocycles and a pair of MgŻOH coordination bonds. This structure was confirmed by an intermolecular 1H―1H nuclear Overhauser effect correlation. However, Form II showing the Qyabsorption at 705 nm was ascribed to an oligomer in which the dimer units are stacked to form an inclined column.