Pyridomycin

Huang et al. identified and characterized the biosynthetic gene cluster for pyridomycin in S. pyridomyceticus NRRL B-2517. Sequence analysis revealed 26 putative orfs (open reading frames). PyrA and PyrU constituted the loading module that initiated the assembly of the pyridomycin backbone. 

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Discovery of Kanamycin, and Establishment oflMC. Chloramphenicol, chlor- and oxy-tetracyclines, and pyridomycin (H. Umezawa, 1967) were active, in in vitro experiments, against strains of tuberculosis, but these drugs, in contrast to streptomycin, were clinically inactive. H. Umezawa... 

S,4S)-4-Amino-3-hydroxy-2-methyl-5-(3-pyridyl)pentanoic acid (8) was isolated as a degradation product from the antimycobacterial antibiotic pyridomycin. " The absolute configuration of the antibiotic was determined by X-ray crystallographic analysis." ... 

Pyridomycin S. pyridomyceticus Antimycobacterial activity Gram-pos. bacteria 520... 

Considerable work has been carried out on the preparation of component parts of chiral macrocycles. The aeid (5) has been prepared for the synthesis of pyridomycin by the procedure outlined in Scheme 3 3 The complete antibiotic antimycin A3 (6) has been synthesized from methyl 2-butyl-2,5-dideoxy-j3-L-arabinofuranoside (7) (Scheme 4), and the C-1 C-9 segment (8) of the... 

The biosynthesis of pyridomycin was first studied by Ogawara. Isotope labeling studies demonstrated that it might involve the assembly of the backbone by a hybrid nonribosomal peptide synthetase (NRPS)/polyketide synthase (PKS) system using 3-hydroxypicolinic acid (3-HPA) as the starting unit (Figure 6.15) [67]. 

Figure 6.15 (a,b) Schematic representation of the pyridomycin biosynthetic gene cluster and... 

Ilicolin H deriv., Y"22.8 C27H32N2O10 Cadacumbine, K"4.11 C27H32N4O8 Pyridomycin, Y26.7... 

One conceivable approach to the amino acid pyridomycin (28) might utilise the aldehydo group of an aldose to generate the carboxyl group of the product. However Kinoshita and Mariyama wisely chose to utilize the glucose skeleton (6 a) in a different way (Scheme 7). 

In order to obtain the tertiary methyl group of pyridomycin, Kino SHiTA and Mariyama took advantage of the fact that additions at the trigonal centre in derivatives such as (24) occur with complete stereoselectivity (82, 91) from the exo-face. The latter (24) was readily obtained from diacetone glucose (6 a) (Scheme 2) via the ketone (23). 

Konotshita, M., and S. Mariyama Synthesis of (2R,3S,4S)-4-Amino-3-hydroxy-2-methyl-5 (3-pyridyl)-pentanoic Acid Present in Antibiotic Pyridomycin. Bull. Soc. Chem. Japan. 48, 2081 (1975). 

C Pyridomycin dihydrobromide monohydrate ethyl acetate solvate (absolute configuration)... 

Streptolidine (473), a guanidinoamino-acid that occurs as a component of the streptothricin group of antibiotics, has been synthesized by way of the lactam form (472) of (2S, 35,4i )-2,3,5-triamino-4-hydroxypentanoic acid (Scheme 154) 936 2R, 35, 45)-4-Amino-3-hydroxy-2-methyl-5-(pyrid-3-yl)pentanoic acid (474), a component of the antibiotic pyridomycin, has been derived from 3-deoxy-l,2 5,6-di-0-isopropylidene-3-C-methyl-a-D-allofuranose by the sequence of reactions outlined in Scheme 155. ... 

Pyrazolines, A6, A2, A29 Pyrethric acid, A35 Pyrethrins, T17, A35 Pyrethrolone, T17 Pyrethrosin, T21 Pyridomycin, Y26 Pyrimidine derivatives, A55, Y21 Pyrocin, A3 5 Pyroclavine, K17... 

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