Add second link to HG bindingDB data

Author: davidlmobley

paper/benchmarkset.tex

@@ -293,7 +293,7 @@ \subsubsection{Cucurbiturils}
 which have been characterized to different extents. 
 Of note, the n=6,7,8 variants accommodate guests of progressively larger size, but are consistent in preferring to bind guests with a hydrophobic core sized to fit snugly into the relatively nonpolar binding cavity, along with at least one cationic moiety (though neutral compounds do bind~\cite{wyman_cucurbituril_2008, lee_deciphering_2015}) that forms stabilizing interactions with the oxygens of the carbonyl groups fringing both portals of the host~\cite{liu_cucurbituril_2005}. 
 Although derivatives of these parent compounds, have been made \cite{Lee:2003:AccountsofChemicalResearch, vinciguerra_synthesis_2015, assaf_cucurbiturils:_2015, Cong:2016:Org.Biomol.Chem.},
-most of the binding data published for this class of hosts pertain to the non-derivatized forms. 
+most of the binding data published for this class of hosts pertain to the non-derivatized forms. A fairly extensive set of data is available in BindingDB at \url{http://bindingdb.org/bind/HostGuest.jsp}.
 
 
 We propose cucurbit[7]uril (CB7) as the basis of one series of host-guest benchmark systems ({\bf Figure~\ref{hosts}}, {\bf Tables~\ref{cb7_benchmark1} and~\ref{cb7_benchmark2}}).