Disclaimer: The findings discussed are lab based and further studies need to be done.
The reason maple syrup is a great alternative sweetener is due to a molecule called quebecol. This compound is known to have antioxidant properties, which has shown to decrease the risk of many diseases and cancers. The University of Rhode Island researchers were able to find this new compound by extracting and analyzing molecules in Canadian Maple Syrup.
Further research on quebecol done at this institution suggests that the molecule is formed within the processing events that make maple sap into maple syrup. This suggests that maple syrup, through its processing, actually holds more health benefits than other maple products. Despite this, the maple extraction still shows other natural forming and antioxidant compounds, that are similar to quebecol. Either way, maple syrup is full of these compounds that contribute to many health benefits.
Reference: Li, L.; Seeram, N.P. Quebecol, a novel phenolic compound isolated from Canadian maple syrup. Journal of Functional Foods, 2011, 3, 125-128. https://web.uri.edu/maple/quebecol-a-novel-phenolic-compound-isolated-from-canadian-maple-syrup/