736. Aplasmomycin

Nomenclature

CAS number: 61230-25-9
(T-4)-[(1R,2R,5S,6R,8S,9E,12R,14S,17R,18R,19R,22S,23R,25S,26E,29R,31S,34R)-1,2,18,19-Tetra(hydroxy-κO)-12,29-dihydroxy-6,13,13,17,23,30,30,34-octamethyl-4,7,21,24,35,37-hexaoxapentacyclo[29.3.1.15.8.114,18.122,25]octatriaconta-9,26-diene-3,20-dionato(4)]borate(1) sodium (1:1); ICI-122378.
C40H60BNaO14; mol wt 798.70.
C 60.15%, H 7.57%, B 1.35%, Na 2.88%, O 28.04%.

Description and references

Antibiotic produced by Streptomyces griseus strain SS-20, obtained from shallow sea mud: Y. Okami et al., J. Antibiot. 29, 1019 (1976); eidem, JP Kokai 77 108901 (1977 to Microbiochem. Res. Found.), C.A. 88, 35843 (1978). It inhibits the growth of gram-positive bacteria in vitro and is active vs Plasmodium berghei in vivo. Aplasmomycin is a symmetrical dimer related to boromycin, q.v., the only other known natural product that contains boron. Structure, x-ray crystallography: H. Nakamura et al., J. Antibiot. 30, 714 (1977). Total synthesis of (+)-form: E. J. Corey et al., J. Am. Chem. Soc. 104, 6816, 6818 (1982); T. Nakata et al., Tetrahedron Lett. 27, 6341, 6345 (1986); J. D. White et al., J. Am. Chem. Soc. 108, 8105 (1986). Use as growth promotant in ruminants: D. H. Davies et al., EP 2893; eidem, US 4225593 (1979, 1980 both to ICI). Two minor components, aplasmomycins B and C, have also been isolated from the fermentation; both aplasmomycin and aplasmomycin B show ionophoric properties, mediating net K+ transport across a bulk phase: K. Sato et al., J. Antibiot. 31, 632 (1978). NMR analysis of aplasmomycin and deboroaplasmomycin: T. S. S. Chen et al., ibid. 33, 1316 (1980). Comparative anti-anaerobic activity of aplasmomycin: K. Watanabe et al., Antimicrob. Agents Chemother. 19, 519 (1981). Structural studies: T. J. Stout et al., Tetrahedron 47, 3511 (1991). Review of biosynthetic studies: H. G. Floss, C. Chang in Antibiotics IV, J. W. Corcoran, Ed. (Springer-Verlag, New York, 1981) pp 203-210.

Chemical structure

Properties

Colorless needles, mp 283-285° (dec). [α]D22 +225° (c = 1.24 in chloroform). Very lipophilic. Practically insol in water. LD50 i.p. in mice: 125 mg/kg (Okami).

Derivative

Silver salt.
C40H60AgBO14; mol wt 883.58.
C 54.37%, H 6.84%, Ag 12.21%, B 1.22%, O 25.35%.

Properties

Colorless needles, mp 218-220°. [α]D23 +194° (c = 0.34 in chloroform).

Use

Growth promotant in ruminants.