ChEBI: (R)-3-[(R)-3-hydroxybutanoyloxy]butanoic acid is a carboxylic ester arising from the formal condensation of the alcoholic hydroxy group of one molecule of (3R)-3-hydroxybutanoic acid with the the carboxylic acid group of another. It is a sex pheromone in the European spider Linyphia triangularis. It has a role as a pheromone and a fungal metabolite. It is a carboxylic ester and a (3R)-3-hydroxybutanoic acid oligomer. It is functionally related to a butyric acid. It is a conjugate acid of a (R)-3-[(R)-3-hydroxybutanoyloxy]butanoate.