16. A non-transitory computer readable medium having instructions stored thereon, wherein the instructions, when executed by a processor, cause the processor to for each source file in a first collection of source files: parse the respective source file to extract one or more chemical structures, compare the one or more chemical structures to chemical structures stored in at least one dictionary, wherein comparing the one or more chemical structures comprises identifying one or more matching chemical structures, and each dictionary of the at least one dictionary comprises a hierarchical listing of chemical structures; associate, with the respective source file, the one or more matching chemical structures; generate a first virtual relational network comprising the source files in the first collection, wherein the first virtual network comprises: one or more nodes, wherein each node of the one or more nodes represents a particular matching chemical structure of the one or more matching chemical structures associated with a particular source file of the source files in the first collection, and one or more links, wherein each link represents a connection between a pair of nodes, wherein each node of the pair of nodes is associated with a common chemical structure; and compare the first virtual relational network to a second virtual relational network, wherein comparing comprises identifying at least one of a) one or more nodes and b) one or more links common to both the first virtual relational network and the second virtual relational network, wherein the second virtual relational network is created from a second collection of source files different than the first collection of source files; and the first virtual relational network and the second virtual relational network share at least one common dictionary, wherein the at least one dictionary comprises the at least one common dictionary.
16. A non-transitory computer readable medium having instructions stored thereon, wherein the instructions, when executed by a processor, cause the processor to for each source file in a first collection of source files: parse the respective source file to extract one or more chemical structures, compare the one or more chemical structures to chemical structures stored in at least one dictionary, wherein comparing the one or more chemical structures comprises identifying one or more matching chemical structures, and each dictionary of the at least one dictionary comprises a hierarchical listing of chemical structures; associate, with the respective source file, the one or more matching chemical structures; generate a first virtual relational network comprising the source files in the first collection, wherein the first virtual network comprises: one or more nodes, wherein each node of the one or more nodes represents a particular matching chemical structure of the one or more matching chemical structures associated with a particular source file of the source files in the first collection, and one or more links, wherein each link represents a connection between a pair of nodes, wherein each node of the pair of nodes is associated with a common chemical structure; and compare the first virtual relational network to a second virtual relational network, wherein comparing comprises identifying at least one of a) one or more nodes and b) one or more links common to both the first virtual relational network and the second virtual relational network, wherein the second virtual relational network is created from a second collection of source files different than the first collection of source files; and the first virtual relational network and the second virtual relational network share at least one common dictionary, wherein the at least one dictionary comprises the at least one common dictionary. 20. The computer readable medium of claim 16 , wherein the instructions, when executed, cause the processor to: after generating the first virtual relational network, add a new source file to the first collection, parse the new source file to extract one or more additional chemical structures, associate, with the new source file, the one or more additional chemical structures, and regenerate the first virtual relational network, wherein regenerating comprises including the new source file in the first virtual network.