Synthesis of chlorophyll-a homologs by C132-substitutions and their physico- and biochemical properties

In Vitro Hydrolysis of Zinc Chlorophyllide a Homologues by a BciC Enzyme

“…The RT of the product band #2 was different from that of (13 2 R )-methylated compound Zn-1c (band #3 in the gray profile, RT = 17.9 min), which would be produced by the demethoxycarbonylation of Zn-1a , and the mass number of the former’s product was larger by a value of 44 (= CO 2 ) than that of the latter’s. Moreover, the visible spectral, mass, and RT data of band #2 were consistent with those of the authentic sample of Zn-1b (the black profile) obtained by the chemical modification of Chl a , based on Scheme S1 . Thus, the product band #2 was assigned to Zn-1b , prepared by the hydrolysis of Zn-1a .…”

“…Moreover, the visible spectral, mass, and RT data of band #2 were consistent with those of the authentic sample of Zn-1b (the black profile) obtained by the chemical modification of Chl a, based on Scheme S1. 25 Thus, the product band #2 was assigned to Zn-1b, prepared by the hydrolysis of Zn-1a. After incubation for 24 h, the methyl ester substrate at band #1 was fully consumed, with only the hydrolyzed product visible at band #2; however, the further decarboxylated compound at band #3 was not visible (the orange profile).…”

Intramolecular axial α/β-coordination of the 132-terminal pyridyl group to the central zinc atom in chlorophyll-a derivatives

“…All the desired products, H 2 -2/2′(C 1 ) , H 2 -2/2′(C 2 ) , and H 2 -2/2′(C 3 ) , were obtained as 3 : 2 epimeric mixtures, whose epimeric ratios were comparable to those previously reported for the related 13 2 -alkylations of H 2 -1/1′ . 13,16 Flash column chromatography (FCC) followed by precipitation from CH 2 Cl 2 and hexane gave pure samples of H 2 -2/2′(C 1 ) and H 2 -2/2′(C 3 ) in 56% and 37% yields, respectively, whereas H 2 -2/2′(C 2 ) was used for the next step without purification by FCC due to the production of unidentified byproducts that were hard to separate from the desired products by chromatographic techniques.…”

“…[10][11][12] So far, alkyl and ω-alkoxycarbonylalkyl groups have been introduced at the C13 2 -position to produce (13 2 R/S)-epimerically mixed adducts. [13][14][15][16] Similarly, (13 2 R/S)-alkanoic acid tert-butyl ester adducts were synthesized as the starting materials, followed by deprotection and condensation reactions to give non-epimerized products bearing a m-pyridyl terminal that were computationally designed as intramolecular coordinative conformations. An epimeric mixture of the products was separated by using reverse phase (RP) HPLC and their stereochemistry was characterized by 1D/2D NMR.…”

Chlorophyllides: Preparation, Purification, and Application

“…The position of C13 2 in chlorophyll led to the relatively high acidity and high reactivity. At the chiral C13 2 -position, chlorophyll(ide)s are transformed to epimers via stereoinversion and allomers via oxidation [146][147][148]. It is well known that the epimerization and allomerization occur easily under basic conditions and an alcoholic solution [149,150].…”