Simple molecule shows remarkable Alzheimer's reversal in rats ScienceDaily

[eppur_se_muova]

4. Here's that simple compound (L10); L9 and L11 were less successful in rat models.

From https://pubs.acs.org/doi/10.1021/acschemneuro.5c00291

In (b), 4 should have an aldehyde group, not a vinyl group. The oxygen atom isn't showing. In the subsequent step, the 2nd equiv. of amine evidently functions as a reducing agent under basic conditions, converting a C=N double bond to a single bond. Presumably, those familiar with the chemistry of quinolines expect this.

If this compound is approved, its synthesis will be the subject of intense optimization efforts, to make it more quickly, cleanly, and efficiently. The first synthesis of a compound is almost never the best -- these researchers just wanted to get the compound so they could test it. Tweaks can wait.