5-Hydroxymaltol, a derivative of maltol, is a substance that can be found in Penicillium echinulatum.

[1] It is also found in toasted oak[2] and also in honeys from blue gum (Eucalyptus leucoxylon) and yellow box (Eucalyptus melliodora).

[3] This article about a heterocyclic compound is a stub.

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