dihydroxyacetylene

3,4-bis(4-methylpentan-2-yloxy)cyclobut-3-ene-1,2-dione

3,4-bis(3-methoxyphenoxy)cyclobut-3-ene-1,2-dione

3,4-dihexoxycyclobut-3-ene-1,2-dione

3,4-di(butan-2-yloxy)cyclobut-3-ene-1,2-dione