Novel potent 5-HT(1F) receptor agonists: structure-activity studies of a series of substituted N-[3-(1-methyl-4-piperidinyl)-1H-pyrrolo[3,2-b]pyridin-5-yl]amides.
Compound 1a (LY334370), a selective 5-HT(1F) receptor agonist (SSOFRA), inhibited dural inflammation in the neurogenic plasma protein extravasation model of migraine and demonstrated clinical efficacy for the acute treatment of migraine. Although 1a was greater than 100-fold selective over both the 5-HT(1B) and 5-HT(1D) receptors, it exhibited appreciable 5-HT(1A) receptor affinity. Described here is the synthesis and evaluation of a series of pyrrolo[2,3-c]pyridine and pyrrolo[3,2-b]pyridine (2a and 3a) as well as pyrrolo[3,2-d]pyrimidine (4a) analogues of 1a, compounds prepared in an effort to identify SSOFRAs with improved selectivity over other 5-HT(1) receptor subtypes. The pyrrolo[3,2-b]pyridine analogue 3a showed high 5-HT(1F) receptor affinity but offered no improvement in selectivity compared to 1a. However, the C-5 acetamide derivative, 3b, was greater than 100-fold selective over the 5-HT(1A), 5-HT(1B), and 5-HT(1D) receptors. SAR studies of this series determined that alkylamides in particular exhibited high selectivity for the 5-HT(1F) receptor. Replacement at C-5 with other substituents decreased affinity or selectivity. These SAR studies identified SSOFRAs that demonstrated oral activity in the neurogenic plasma protein extravasation model, a model indicative of antimigraine activity.
Filla
Sandra A
SA
Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA. sandra.filla@astrazeneca.com
Mathes
Brian M
BM
Johnson
Kirk W
KW
Phebus
Lee A
LA
Cohen
Marlene L
ML
Nelson
David L
DL
Zgombick
John M
JM
Erickson
Jon A
JA
Schenck
Kathryn W
KW
Wainscott
David B
DB
Branchek
Theresa A
TA
Schaus
John M
JM
D000284:Administration, Oral; D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D002460:Cell Line; D066298:In Vitro Techniques; D008881:Migraine Disorders / Q000188:drug therapy / Q000378:metabolism; D010880:Piperidines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D053284:Polyunsaturated Alkamides; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D011817:Rabbits; D011869:Radioligand Assay; D011985:Receptors, Serotonin / Q000187:drug effects*; D012501:Saphenous Vein / Q000187:drug effects / Q000502:physiology; D017366:Serotonin Receptor Agonists / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013329:Structure-Activity Relationship; D014276:Trigeminal Nerve / Q000378:metabolism; D014661:Vasoconstriction / Q000187:drug effects; D000096642:Receptor, Serotonin, 5-HT1F
D001798:Blood Proteins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D010880:Piperidines; D053284:Polyunsaturated Alkamides; D011725:Pyridines; D011758:Pyrroles; D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists; D000096642:Receptor, Serotonin, 5-HT1F; C476137:N-(3-(1-methyl-4-piperidinyl)-1H-pyrrolo(3,2-b)pyridin-5-yl)acetamide; C476138:N-(3-(1-methyl-4-piperidinyl)-1H-pyrrolo(3,2-b)pyridin-5-yl)propanamide