(1Z)-1-(anilinomethylidene)-7-[(8Z)-8-(anilinomethylidene)-1,6-dihydroxy-3-methyl-7-oxo-5-propan-2-ylnaphthalen-2-yl]-3,8-dihydroxy-6-methyl-4-propan-2-ylnaphthalen-2-one