Chloroquine may interfere with the terminal glycosylation of the ACE2 receptor, potentially inhibiting coronavirus binding and entry into cells.

“one of the things that is suggested for corona virus is that it may indeed be or suggested for chloroquine is that it may be affecting the way that these angiotensin converting to angiotensin converting enzyme to cellular receptors are glycosylated which is the addition of a sugar group to the receptor and that may inhibit viral attachment and entry into the cell”

“suggesting that the terminal glycosylation the addition of the sugar unit to the ACE two transmembrane receptor or the ACE 2 cellular receptor I should say is inhibited partially by chloroquine”