Peridinin

Hoffman, E., et al., 1996. Structural basis of light harvesting by carotenoids Peridinin-chlorophyll-protein from Amphidinium carterae. Science 272 1788-1791. 

The AE reactions on 2,5,5-trisubstituted allyl alcohols have received little attention, due in part the limited utility of the product epoxides. Selective ring opening of tetrasubstituted epoxides are difficult to achieve. Epoxide 39 was prepared using stoichiometric AE conditions and were subsequently elaborated to Darvon alcohol. Epoxides 40 and 41 were both prepared in good selectivity and subsequently utilized in the preparation of (-)-cuparene and the polyfunctoinal carotenoid peridinin, respectively. Scheme 1.6.12... 

Damjanovic, A., Ritz, T. and Schulten, K. (2000). Excitation transfer in the peridinin-chlorophyll-protein of Amphidinium carterae. Biophys. J. 

Waller RF, Patron NJ, Keeling PJ (2006) Phylogenetic history of plastid-targeted proteins in the peridinin-containing dinoflagellate Heterocapsa triquetra. Int J Syst Evol Micr... 

Spino and Frechette reported the synthesis of non-racemic allenic alcohol 168 by a combination of Shi s asymmetric epoxidation of 166 and its organocopper-mediat-ed ring-opening reaction (Scheme 4.43) [74]. Reduction of the ethynyl epoxide 169 with DIBAL-H stereoselectively gave the allenic alcohol 170, which was converted to mimulaxanthin 171 (Scheme 4.44) [75] (cf. Section 18.2.2). The DIBAL-H reduction was also applied in the conversion of 173 to the allene 174, which was a synthetic intermediate for peridinine 175 (Scheme 4.45) [76], The SN2 reduction of ethynyl epoxide 176 with DIBAL-H gave 177 (Scheme 4.46) [77]. 

Scheme 4.45 Total synthesis of peridinine via ring-opening reduction of epoxide 173.

Scheme 18.2 Structure of the allenic carotinoids fucoxanthin (5) and peridinin (6).

To link the two half moieties of the molecule, a Julia-Kocienski olefmation was carried out between the C19 building block 59 (again prepared by syn-SN2 -substitu-tion of a propargylic oxirane with DIBAH) and the C20 building block 60, formed via oxidation of 58 with Mn02 (Scheme 18.19). Although this reaction initially led to the formation of the Z-isomer as the major product, the latter was readily isomerized at room temperature to the desired all-trans-polyene peridinin (6). 

Scheme 18.18 Synthesis of peridinin (5) [59] formation of the key building block 58 (TPP= 5,10,15,20-tetraphenyl-21 H,23H-porphin R = allyl).

Starting 50 years ago, the chemistry of allenic natural products and pharmaceuticals has turned out to be a very attractive and prolific area of interest. Advances in the isolation and characterization of new allenic natural products were accompanied by the establishment of efficient synthetic procedures which also opened up an access to enantiomerically pure target molecules in many cases. Highlights of these developments are the enantioselective total syntheses of the allenic carotinoid peridinin and of the bromoallenes laurallene and isolaurallene. 

Results of investigations on the biosynthesis of neoxanthin (30) and peridinin (6) from 3H- and I4C-labeled mevanolate by the alga Amphidinium carterae are not in accordance with the formation of the exocyclic allene from an alkyne I. E. Swift, B. V. Milborrow, Biochem.J. 1981, 299, 69-74. 

Per = peridinin But-fuco = 19 -butanoyloxyfucoxanthin fuco = fucoxanthin Hex-fuco = 19 -hexanoyloxyfucoxanthin Neo = neoxanthin Viol = violaxanthin Alio = alloxanthin Zea = zeaxanthin Chi b = chlorophyll-b DV chi a = divinyl chlorophyll-a. 

Carotenoids Peridinin Fucoxanthin 19 -butanoyloxyfucoxanthin 19 -hexanoyloxyfucoxanthin Alloxan thin Prasinoxanthin Lutein Zeaxanthin Dinoflagellates Diatoms Pelagophytes Haptophytes Cryptophytes Prasinophytes Chlorophytes Cyanobacteria, chlorophytes... 

Dinoflagellates Peridinin-containing phytoplankton characterized by a "rotating" swimming movement produced by the combined action of their flagellae. 

Tetraterp. carotenoids/xanthophvlls peridinin in marine and freshw. Dinofl., except of genus Gymnodittium Shimizu 1996. 

Absorption spectra of peridinin in different solvents are shown in Fig. 2a. In the nonpolar solvent M-hexane, the absorption spectrum exhibits the well-resolved structure of vibrational bands of the strongly allowed S0-S2 transition with the 0-0 peak located at 485 nm. In polar solvents, however, the vibrational structure is lost and the absorption band is significantly wider. In addition, there are also differences between the various polar solvents. Although the loss of vibrational structure is obvious, a hint of shoulder is still preserved in methanol and acetonitrile, but in ethylene glycol and glycerol the absorption spectrum is completely structureless with a broad red tail extending beyond 600 nm. 

Fig. 2. (a) Absorption spectra of peridinin in n-hexane (dot), acetonitrile (dash-dot), methanol (solid), ethylene glycol (dash) and glycerol (dash-dot-dot). All spectra are normalized, (b) Kinetic traces of peridinin emission in different solvents measured at 730 nm. 1) n-hexane (156 ps), 2) tetrahydrofuran (77 ps), 3) 2-propanol (54 ps), 4) methanol (10.5 ps). All traces are normalized. 

Fig, 3. Transient absorption spectra of peridinin in methanol recorded in the visible (a) and the near-infrared (b) spectral regions after excitation at 490 nm in methanol (full squares) and at 535 nm in ethylene glycol (open squares). The transient absorption spectra in the visible region are normalized to the ESA maximum, while the near-infrared spectra are normalized to a maximum of the ICT emission. 

Early work on peridinin demonstrated that its structure leads to breaking of the idealized C2h symmetry resulting in relatively strong fluorescence from the Si state [16], Recent studies demonstrated that the intensity of the peridinin Si emission depends on solvent polarity [8,9], and time-resolved studies revealed that the polarity-dependent change in the Si emission yield... 

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