D-galactaro-1,5-lactone => D-galactaro-1,4-lactone
d-galactaro-1,5-lactone => d-galactaro-1,4-lactone
D-galactaro-1,5-lactone => D-galactaro-1,4-lactone
d-galactaro-1,5-lactone => d-galactaro-1,4-lactone