124
This compound was first isolated in 1953 from Penicillium strains (Pidacks et al.
1953). Figure 8.6 shows the presence of three bidentate hydroxamate ligands in
coprogen (4) that help to hold the ferric ion (Fe
3+
) firmly and can expect other trihydroxamate copragens (Fig. 8.7) form similar Fe
3+
complexes. In most of the trihydroxamate coprogen members, the N
2
substitution is acyl group.
The species Epicoccum purpurascens (Syn. E. nigrum) belongs to the family
Leptosphaeriaceae which is a rich source of siderophores with four major constituents of 87% of the total weight, ferricrocin, coprogen, triornicin, and isotriornicin,
and among the compound neocoprogen I (triornicin) (9) is having slight antitumor
activity. The compounds 9 and isotriornicin (10) are positional isomers with the
exchange of acetyl and (E)-5-hydroxy-3-methyl-2-pentenoyl hydroxamate groups
(Frederick et al. 1982). Compound 10 is the first example of trihydroxamate siderophore in the solid state with Δ-trans geometry of iron coordination (Hossain
et al. 1987).
Table 8.1 Fungal hydroxamate coprogen siderophores
Name of the siderophore Fungal species
References
(i) Dihydroxamate
members
Rhodotorulic acid (2)
Ustilago inflorescentiae
Atkin and
Neilands (1968)
and Muller et al.
(1985)
Dimerum acid (3)
Fusarium dimerum
Diekmann (1970)
(ii)
Trihydroxamate
members
Coprogen (4)
Penicillium sp.
Pidacks et al.
(1953)
Coprogen B (5)
Fusarium dimerum
Diekmann (1970)
Hydroxycoprogen (6)
Alternaria longipes
Jalal and Helm
(1989)
Hydroxyneocoprogen I (7) A. longipes
Jalal and Helm
(1989)
Hydroxyisoneocoprogen I
(8)
A. longipes
Jalal and Helm
(1989)
Isoneocoprogen I or
Triornicin (9)
Epicoccum purpurascens
(Syn. E. nigrum)
(triornicin)
Frederick et al.
1981)
Isotriornicin or
Neocoprogen I (10)
Epicoccus purpurascens
(Isotriornicin) and
Curuularia lunata
(Neocoprogen I)
Frederick et al.
(1982) and
Hossain et al.
(1987)
Neocoprogen II (11)
Curuularia lunata
Hossain et al.
(1987)
N
α -dimethyl coprogen (12) A. longipes
Jalal et al. (1988)
N
α -dimethyl neocoprogen
I (13)
A. longipes
Jalal et al. (1988)
N
α -dimethyl
isoneocoprogen I (14)
A. longipes
Jalal et al. (1988)
Palmitoylcoprogen (15)
Trichoderma strain
Anke et al. (1991)
M. S. A. Shukkoor and S. I. Khalivulla
This compound was first isolated in 1953 from Penicillium strains (Pidacks et al.
1953). Figure 8.6 shows the presence of three bidentate hydroxamate ligands in
coprogen (4) that help to hold the ferric ion (Fe
3+
) firmly and can expect other trihydroxamate copragens (Fig. 8.7) form similar Fe
3+
complexes. In most of the trihydroxamate coprogen members, the N
2
substitution is acyl group.
The species Epicoccum purpurascens (Syn. E. nigrum) belongs to the family
Leptosphaeriaceae which is a rich source of siderophores with four major constituents of 87% of the total weight, ferricrocin, coprogen, triornicin, and isotriornicin,
and among the compound neocoprogen I (triornicin) (9) is having slight antitumor
activity. The compounds 9 and isotriornicin (10) are positional isomers with the
exchange of acetyl and (E)-5-hydroxy-3-methyl-2-pentenoyl hydroxamate groups
(Frederick et al. 1982). Compound 10 is the first example of trihydroxamate siderophore in the solid state with Δ-trans geometry of iron coordination (Hossain
et al. 1987).
Table 8.1 Fungal hydroxamate coprogen siderophores
Name of the siderophore Fungal species
References
(i) Dihydroxamate
members
Rhodotorulic acid (2)
Ustilago inflorescentiae
Atkin and
Neilands (1968)
and Muller et al.
(1985)
Dimerum acid (3)
Fusarium dimerum
Diekmann (1970)
(ii)
Trihydroxamate
members
Coprogen (4)
Penicillium sp.
Pidacks et al.
(1953)
Coprogen B (5)
Fusarium dimerum
Diekmann (1970)
Hydroxycoprogen (6)
Alternaria longipes
Jalal and Helm
(1989)
Hydroxyneocoprogen I (7) A. longipes
Jalal and Helm
(1989)
Hydroxyisoneocoprogen I
(8)
A. longipes
Jalal and Helm
(1989)
Isoneocoprogen I or
Triornicin (9)
Epicoccum purpurascens
(Syn. E. nigrum)
(triornicin)
Frederick et al.
1981)
Isotriornicin or
Neocoprogen I (10)
Epicoccus purpurascens
(Isotriornicin) and
Curuularia lunata
(Neocoprogen I)
Frederick et al.
(1982) and
Hossain et al.
(1987)
Neocoprogen II (11)
Curuularia lunata
Hossain et al.
(1987)
N
α -dimethyl coprogen (12) A. longipes
Jalal et al. (1988)
N
α -dimethyl neocoprogen
I (13)
A. longipes
Jalal et al. (1988)
N
α -dimethyl
isoneocoprogen I (14)
A. longipes
Jalal et al. (1988)
Palmitoylcoprogen (15)
Trichoderma strain
Anke et al. (1991)
M. S. A. Shukkoor and S. I. Khalivulla