unreacted starting material was successfully isolated. In the case of Sulfaphenazole, the pyrazole moiety bearing a sulfonamide group in the 5 position served as a suitable directing group, yielding analogue 3d. Worth noting is the improved tolerance of the aniline compared to the functional group tolerance study (Table ), presumably due to different electronic properties of the nitrogen affected by the para sulfonamide group. A case of unexpected selectivity was observed with Telmisartan, where product 3e, resulting from the coordination of the N-methylbenzimidazole, was obtained as a single regioisomer, with no product formation observed from the carboxylate coordination. This is also the only example where we observed the formation of product with a 1,2,3 substitution pattern. We rationalize the observed selectivity as a result of the steric arrangement of the substrate, with the ortho substituent of the benzoic acid moiety decreasing its reactivity, and the fused ring system on the 3 position decreasing steric hindrance and allowing functionalization in a 1,2,3 layout. The imine moiety of Diazepam facilitated the amination of the phenyl core. Both monofunctionalized 3f and difunctionalized 3f´ were successfully isolated. It is important to note that the products were isolated directly from the LSF informer library at 0.02 mmol scale, in quantities sufficient for complete characterization. Lumacaftor was successfully functionalized in NMP with complete selectivity for the carboxylate-directed amination. While with relatively low conversion, the 2-acylanilido pyridine structural motif was tolerated. A significant amount of unreacted starting material was also recovered. The product of carboxylate-directed C-H amination of Repaglinide 3h was successfully isolated on the 0.02 mmol screening scale. The tolerance of the tertiary amine moiety is rationalized by its anilinic nature. A powerful example of the utility of the herein described amination protocol is demonstrated with the functionalization of Paclitaxel. This complex natural product contains a number polar and protic functional groups, sensitive ester groups, a strained oxetane ring and an unsaturation, all of which pose a potential challenge for LSF methods. While 3i could be obtained with 20% isolated yield under standard conditions, the use of one equivalent of acid additive allowed for increasing the isolated yield to 72%. This result, to the best of our knowledge, presents the highest yielding example of Paclitaxel C-H functionalization reported to date. The observation of the positive effect of carboxylic acid additives on conversions with substrate bearing amide directing groups was first observed with the example of Bezafibrate. The conversion to 3j was much higher than conversions of corresponding amides in the DG informer library. This unexpected observation further strengthens the case for LSF informer libraries, as the combinations of structural motifs directly aided methodology development.