- Isomerization of uroporphyrinogen I octamethyl ester through spiro- pyrrolenine intermediate
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Treatment of uroporphyrinogen I octamethyl ester with 2- mercaptobenzothiazolylmethyl pyrrole derivative in the presence of silver (I) trifrate under anaerobic condition in dichloromethane for 20 h, followed by aerial oxidation of the products, gave a statistical mixture of uroporphyrin I~IV octamethyl esters. It was proposed that this transformation proceeds through a spiro-pyrrolenine as a key intermediate.
- Takakura, Hiroyuki,Nomura, Keishi,Tanino, Hideo,Okada, Kunisuke
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- Identification of tetrapyrrole compounds excreted by Rhodobacter sphaeroides and sources of the methyl hydrogens of bacteriochlorophyll a biosynthesized by R. sphaeroides, based on13C-NMR spectral analysis of coproporphyrin III tetramethyl ester
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Red-fluorescent tetrapyrrole compounds excreted by Rhodobacter sphaeroides into the culture broth were concluded to be coproporphyrinogen (Copro'gen) III and uroporphyrinogen (Uro'gen) I, based on the 13C-NMR spectral identification of coproporphyrin (Copro) III tetramethyl ester and uroproporphyrin (Uro) I octamethyl ester. The sources of the methyl hydrogens of bacteriochlorophyll a were established by analysis of the 13C-NMR spectra of 2H,13C-Copro III tetramethyl ester chemically derived from 2H,13C-Copro'gen III biosynthesized through the feeding of δ-amino[2-13C]levulinic acid (ALA) to R. sphaeroides in medium containing 50% 2H2O. We confirmed the previous finding that one of the methyl hydrogens was derived from water in the medium during decarboxylation of four acetyl side chains of Uro'gen III to generate Copro'gen III. It was further shown that the other hydrogen atoms, previously reported to be derived from methylene hydrogens at C-2 of ALA, had been exchanged with hydrogen of water in the medium in the biosynthetic pathways leading from ALA to Copro'gen III.
- Iida, Katsumi,Nakamura, Masayuki,Hanamitsu, Hiroshi,Kajiwara, Masahiro
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- Biosynthesis of corrinoids and porphyrinoids. VII. Uroporphyrins from Saccharopolyspora erythraea
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Cultured broth of Saccharopolyspora erythraea shows a strong red fluorescence. The main fluorescent component was identified as uroporphyrin I by FAB-MS and 1H-NMR. This was confirmed by a feeding experiment using [5-13C]aminolevulinic acid.
- Kajiwara,Hara,Mizutani,Kondo
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- Synthesis of a linear α-hydroxymethyl-pentapyrrole derivative and its cyclization to uroporphyrinogens
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A linear pentapyrrole bearing α-hydroxymeythyl group in the terminal was synthesized by the stepwise coupling of α-free pyrrole with azafulvenium ion 6. When it was treated with a catalytic amount of p-toluensulfonic acid under anaerobic condition, followed by aerial oxidation of the products, a statistical mixture of uroporphyrin I-IV octamethyl esters was obtained. It is proposed that this transformation proceeds through a spiro-pyrrolenine as a key intermediate. (C) 2000 Elsevier Science Ltd.
- Okada, Kunisuke,Takakura, Hiroyuki,Nomura, Keishi,Saburi, Kiyoshi
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p. 2915 - 2918
(2007/10/03)
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- SYNTHESIS OF UROPORPHYRIN-III, AND RELATED HEPTA- AND PENTA-CARBOXYLIC PORPHYRINS BY MODIFICATIONS OF THE MACDONALD METHOD
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A modification of the MacDonald route has been developed in which all four pyrrole units of uroporphyrin-III have been derived from the same conveniently prepared starting pyrrole.Related hepta- and penta-carboxylic porphyrins have also been synthesised by condensation of appropriate α-formyl pyrromethane-α'-carboxylic acids; in each case other porphyrins with different numbers of acidic side-chains were also produced but the desired products were easily separated (as their methyl esters) by h.p.l.c.
- Chakrabarty, M.,Ali, S. A.,Philip, G.,Jackson, A. H.
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p. 1199 - 1204
(2007/10/02)
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