A thorough investigation of the challenging Pd-catalyzed fluorination of five-membered heteroaryl bromides is presented. Crystallographic studies and density functional theory (DFT) calculations suggest that the challenging step of this transformation is C-F reductive elimination of five-membered heteroaryl fluorides from Pd(II) complexes. On the basis of these studies, we have found that various heteroaryl bromides bearing phenyl groups in the ortho position can be effectively fluorinated under catalytic conditions. Highly activated 2-bromoazoles, such as 8-bromocaffeine, are also viable substrates for this reaction.
Provided is a 2H-chromene compound or a derivative thereof which has an excellent S1P1 agonist action. The 2H-chromene compound or derivative is particularly useful for preventing and/or treating a disease induced by undesirable lymphocyte infiltration or a disease induced by abnormal proliferation or accumulation of cells.
Provided is a compound which has an excellent S1P1 agonist action, and is useful particularly as an active ingredient for an agent for preventing and/or treating a disease induced by undesirable lymphocyte infiltration or a disease induced by abnormal proliferation or accumulation of cells. According to the present invention, a 2H-chromene compound or a derivative thereof which has an excellent S1P1 agonist action, and is useful particularly as an active ingredient of an agent for preventing and/or treating a disease induced by undesirable lymphocyte infiltration or a disease induced by abnormal proliferation or accumulation of cells can be provided. The 2H-chromene compound and a derivative thereof which are the compounds of the present invention have an S1P1 agonist action, and can be used particularly for prevention and/or treatment of a disease induced by undesirable lymphocyte infiltration or a disease induced by abnormal proliferation or accumulation of cells.