Abstract
Methyl pheophorbide-a/a′ derivatives covalently linked with oligomethylene chains at the 3-CH2OCO– and 132-COO– moieties in a molecule were prepared by modifying chlorophyll-a through intramolecular ring-closing metathesis of vinyl groups. At least, a C10-length between the 33- and 134-positions was necessary for the cyclization and connection of a C12-strap was the most suitable to achieve the highest closure yield. The oligomethylene chain in 132 R-epimers derived from methyl pheophorbide-a covered the α-face of the chlorin π-plane and the strap in the corresponding 132 S-epimers protected the β-face. Synthetic 132 R-epimer with a dodecamethylene chain gave a flat chlorin π-plane, while the decamethylene chain in the 132 R-epimer distorted the π-system due to its shorter linkage. The distortion by strapping in the 132 R-epimer induced a slight blue-shift of Qy peak in dichloromethane. CD spectra of the 132 R-epimers were similarly dependent on the chain length, i.e., the distortion of π-plane. Visible absorption and CD spectra of all the strapped 132 S-epimers were almost identical and only slightly different from those of the unstrapped. The strapping in the 132 S-epimers shifted the Qy peak bathochromically.
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Abbreviations
- CD:
-
Circular dichroism
- CH:
-
Catalytic hydrogenation
- CMPI:
-
2-Chloro-1-methylpyridinium iodide
- DMAP:
-
4-(N,N-Dimethylamino)pyridine
- EDC:
-
1-Ethyl-3-[3-(N,N-dimethylamino)propyl]carbodiimide (water-soluble carbodiimide)
- FCC:
-
Flash column chromatography
- HPLC:
-
High performance liquid chromatography
- NMR:
-
Nuclear magnetic resonance
- RCM:
-
Ring-closing metathesis
- RP:
-
Reverse-phase
References
Balaban TS, Braun P, Hättig C, Hellweg A, Kern J, Saenger W, Zouni A (2009) Preferential pathways for light-trapping involving β-ligated chlorophylls. Biochim Biophys Acta 1787:1254–1265
Cogdell RJ, Gall A, Köhler J (2006) The architecture and function of the light-harvesting apparatus of purple bacteria: from single molecules to in vivo membranes. Q Rev Biophys 39:227–324
Frolov D, Marsh M, Crouch LI, Fyfe PK, Robert B, van Grondelle R, Hadfield A, Jones MR (2010) Structural and spectroscopic consequences of hexacoordination of a bacteriochlorophyll cofactor in the Rhodobacter sphaeroides reaction center. Biochemistry 49:1882–1892
Furukawa H, Oba T, Tamiaki H, Watanabe T (2000) Effect of C132-stereochemistry on the molecular properties of chlorophylls. Bull Chem Soc Jpn 73:1341–1351
Hoober JK, Eggink LL, Chen M (2007) Chlorophylls, ligands and assembly of light-harvesting complexes in chloroplasts. Photosynth Res 94:387–400
Ishikita H, Loll B, Biesiadka J, Galstyan A, Saenger W, Knapp EW (2005) Tuning electron transfer by ester-group of chlorophylls in bacterial photosynthetic reaction center. FEBS Lett 579:712–716
Kosaka N, Tamiaki H (2004) Synthesis of a novel cyclic chlorophyll hetero-dyad as a model compound for stacked chlorophylls found in photosynthetic systems. Eur J Org Chem 2325–2330
Kureishi Y, Tamiaki H (1998) Synthesis and self-aggregation of zinc 20-halogenochlorins as a model for bacteriochlorophylls-c/d. J Porphyr Phthalocyanines 2:159–169
Oba T, Tamiaki H (1999) Why do chlorosomal chlorophylls lack the C132-methoxycarbonyl moiety? An in vitro model study. Photosynth Res 61:23–31
Oba T, Tamiaki H (2005) Effects of peripheral substituents on diastereoselectivity of the fifth ligand binding to chlorophylls, and nomenclature of the asymmetric axial coordination sites. Bioorg Med Chem 13:5733–5739
Röder B, Büchner M, Rückmann I, Senge MO (2010) Correlation of photophysical parameters with macrocycle distortion in porphyrins with graded degree of saddle distortion. Photochem Photobiol Sci 9:1152–1158
Sasaki S, Mizoguchi T, Tamiaki H (2005a) Synthesis of strapped zinc chlorophyll derivatives and their complexation with a single axial ligand. Tetrahedron 61:8041–8048
Sasaki S, Takebe H, Mizoguchi T, Tamiaki H (2005b) Synthesis of stereospecifically face-protected chlorophyll derivatives. Tetrahedron Lett 46:7687–7689
Senge MO, MacGowan SA (2011) The structural chemistry of isolated chlorophylls, chap 61. In: Kadish KM, Smith KM, Guilard R (eds) Handbook of porphyrin science, vol 13. World Scientific, Singapore, pp 253–297
Tamiaki H, Takeuchi S, Tsudzuki S, Miyatake T, Tanikaga R (1998) Self-aggregation of synthetic zinc chlorins with a chiral 1-hydroxyethyl group as a model for in vivo epimeric bacteriochlorophyll-c and d aggregates. Tetrahedron 54:6699–6718
Tamiaki H, Nagata Y, Tsudzuki S (1999) Synthesis of trifluoromethyl-porphyrins and chlorins. Eur J Org Chem 2471–2473
Tamiaki H, Shibata R, Mizoguchi T (2007) The 17-propionate function of (bacterio)chlorophylls: biological implication of their long esterifying chains in photosynthetic systems. Photochem Photobiol 83:152–162
Tamiaki H, Kotegawa Y, Mizutani K (2008) Rotational deviation of 3-acetyl group from cyclic tetrapyrrole π-plane in synthetic bacteriochlorophyll-a analogs by 20-substitution. Bioorg Med Chem Lett 18:6037–6040
Acknowledgments
We thank Dr. Yasuhiko Kureishi for assistance in molecular modeling calculation. This work was partially supported by a Grant-in-Aid for Scientific Research (A) (No. 22245030) (to HT) from the Japan Society for the Promotion of Science (JSPS) and for Young Scientists (B) (No. 21750154) (to SS) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of the Japanese Government.
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Tamiaki, H., Takebe, H., Sasaki, Si. et al. Synthesis of oligomethylene-strapped chlorophyll derivatives and optical properties of their stereoisomers in a solution. Photosynth Res 111, 1–8 (2012). https://doi.org/10.1007/s11120-010-9616-y
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DOI: https://doi.org/10.1007/s11120-010-9616-y