Primary metabolites, synthesis

Metabolism studies of methoprene in nonaquatic organisms have provided background data which must be considered prior to discussing the fate of methoprene in aquatic systems. All nonaquatic metabolic studies reported to date have utilized [5-1 C]methoprene. The location of radiocarbon was selected both for ease of synthesis and for anticipated metabolic stability. However, studies in plants and bovines (25, 30, 31) revealed many presumed "metabolites" to be radiolabeled natural products, or "nonmetabolite residues". Primary metabolites of methoprene resulting from ester cleavage and/or (O-demethylation have been... 

In another study, an enantioselective assay for the analysis of the enantiomer composition of monomethyl 4-(2, 3 -dichlorophenyl)-2,6-dimethyl-l,4-dihydropyridine-3,5-dicarboxylic acid on the tBuCQN-CSP was proposed (Rs = 3.4) [49], This chiral carboxylic acid is the synthesis intermediate and the primary metabolite... 

The 2,3-dichloro-4-hydroxyphenyl derivative of aripiprazole was prepared to confirm the structure of a primary metabolite of aripiprazole (Scheme 21). The synthesis began with the protection of 4-bromo-2,3-dichlorophenol as its benzyl ether 71. Palladium-catalyzed amination of 71 with piperazine proceeded regioselectively in excellent yield. Alkylation of the piperazine 72 with 69 in the presence of K2CO3 and... 

Primary metabolite Immobilized organelle first step in biophotolysis of water Immobilized algal cells Biological nitrogen fixation Antibiotic synthesis secondary metabolite Concentration of plutonium from waste waters (bioadsorption)... 

Primary metabolites can originate from fundamental processes photosynthesis, glycolysis, and the citric acid cycle (Krebs cycle). They represent biosynthetic intermediates useful as building blocks for the synthesis of secondary metabolites. The latter can be synthesized through a combination of various building blocks (Figure 1.3) ... 

Demain AL, Scanchez S. Microbial synthesis of primary metabolites Current advances and future prospects. In Fermentation Microbiology and Biotechnology, El-Mansi EMT, Bryce CFA, Demain AL, Allman AR, Eds. CRC, New York, pp. 99—130. 

Moreover, when primary metabolites are produced, it is difficult to distinguish the amount of substrate used for cell growth from that used for product synthesis hence, ijc and Ysp are simply lumped into Ysc and Equation 7.25 is simplified to... 

Despite great diversity in form and function, the terpenoids are unified in their common biosynthetic origin. The biosynthesis of all terpenoids from simple, primary metabolites can be divided into four overall steps (a) synthesis of the fundamental precursor IPP (b) repetitive additions of IPP to form a series of prenyl diphosphate homologs, which serve as the immediate precursors of the different classes of terpenoids (c) elaboration of these allylic prenyl diphosphates by specific terpenoid synthases to yield terpenoid skeletons and (d) secondary enzymatic modifications to the skeletons (largely redox reactions) to give rise to the functional properties and great chemical diversity of this family of natural products. As bacosides are triterpenoid derivatives, they may probably foUow the common biosynthetic pathway of terpenoid production [40]. 

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