Ratio: Reactant ratio is considered as the number of cycles of the reaction. Zero (0) means an infinite number of cycles. This consideration is also feasible when only one reagent can be set in a reaction. For example, a reaction on a primary amine group will be repeated until all hydrogens are substituted if the ratio coefficient is 0 and will be stopped at a secondary amine if the coefficient is 1.

Product standardization: You can beautify the resulting compounds with post-standardization. Click on "Edit" to locally set the preferred Standardizer configuration, or select "Browse..." to load a Standardizer configuration file.

Generate unsuccessful reactions (in case of Reaction output type): If a reaction doesn't yield product, the reaction equation is shown but the product will be an empty structure in the output file.

Unambiguous only: Only those reactions are completed that lead to exclusively one possible product list. If there are more than one product lists, then no result will be returned.

Ignore reaction rules: The set rules of a reaction are ignored (especially for testing).

Check "Reactivity and exclude" if you want Reactor to ignore the set reactivity and exclude rules;
Check "Selectivity" if you want Reactor to ignore any set Selectivity rule.

Included products: Unchecked products will not be generated (e.g., in Friedel-Crafts acylation to discard eliminated HCl).