306
MAURICE WELSCH
CH 3 OH OH
CH 2
Ο Ο
I
3 I
I
II
CH 3 —CH 2 —CH—CH-C—CH=CH-CH—C-CH 2 —CH 2 -
ΗΟ—C=0
Alte mar ic acid
(Cm)
2. Polyenes and Polyynes in Antibiotics
A large number of antibiotics, very likely acetate derived, are characterized by the presence of several ethylenic or/and acetylenic bonds.
They are often produced together with related substances devoid of antibiotic activity.
Polyynes, although they are found in higher plants (for instance,
the antifungal capillin from Artemisia capiUaris), lower fungi, and actinomycetes, are especially frequent as metabolic products of basidiomycetes.
Examples are:
agrocybin from Agrocybe dura,
HOCH 2 —C=C—C=C—C=C—CONH 2
diatretyne 1 (inactive);
COOH—CH=CH—feC—C=C—CONH 2
diatretyne 2 or nudic acid;
COOH—CH=CH—C=C—C=C—C=N
diatretyne 3,
COOH—CH=CH—C=C—C=C—C=C—CH 2 OH
all from Clitocybe diatreta. It has been remarked that the latter substance
bears some resemblance to the antibiotic principle of the royal jelly
of bees:
COOH—CH=CH—(CH 2 ) 6 —CH 2 OH
The several quadrifidins, from Coprinus quadrifidus, and biformin, from
Polyporus biformis, belong in the same category.
Nemotin,
ι—
0
—I
HC=C—C=C—CH=C=CH—CH—CH 2 —CH 2 —CO