NKP608 is a non-peptidic derivative of 4-aminopiperidine which acts as a selective, specific and potent antagonist at the neurokinin-1 (NK-1) receptor both in vitro(IC50=2.6 nM) and in vivo.

Nifenalol is a beta-adrenoceptor antagonist.

NFEPP is a novel potent, selective pH-dependent μ-opioid receptor (MOR) agonist with a low pKa, shows significantly lower affinity compared with fentanyl at pH 7.4.

Netazepide (YF476, Sograzepide) is a potent, selective and orally active gastrin/CCK-2 antagonist with IC50 of 0.1 nM.

Nedocromil is an inhaled anti-inflammatory agent for the preventive management of asthma.

Nebivolol hydrochloride is a highly selective β1-adrenoceptor antagonist

Naftopidil is an α-1-Adrenergic receptor antagonist and an antihypertensive.

MTEP Hcl is a potent, selective and non-competitive mGlu5 antagonist with IC50 and Ki of 5 nM and 16 nM, respectively.

MRS1186 is a potent and selective human Adenosine A3 receptor (hA3AR) antagonist, with a Ki of 7.66 nM.

Mozavaptan (OPC31260) is a orally effective, nonpeptide vasopressin V2 receptor antagonist with an IC50 of 14 nM.

MLS6585 is a novel positive allosteric modulator of the D1 dopamine receptor, potentiatse dopamine-stimulated G-protein- and β-arrestin-mediated signaling and increase the affinity of dopamine for the D1 receptor with low micromolar potencies..

MLR-1023 is a chemical compound which inhibits acid secretion in animal models and also acts as a bronchodilator in histamine-challenged animals.

MK-8318 (MK8318) is a potent, selective, orally available CRTh2 receptor antagonist with Ki of 5 nM, shows nM potency in functional assay (cAMP IC50=8 nM, β-Arrestin IC50=3.5 nM.

MK-6892 is a highly potential GPR109A agonist with Ki value of 4.0 nM.

MK-3697 is a third insomnia drug, currently being developed by Merck. MK-3697 is a potent and selective Orexin receptor antagonist with Ki = 0.95 nM.

MK-3207 is a potent and orally bioavailable CGRP receptor antagonist (IC50= 0.12 nM; Ki value= 0.024 nM); highly selective versus human AM1, AM2, CTR, and AMY3.

MK-2894 is a highly potent and selective second generation EP4 antagonist.

MK-0974(Telcagepant) is a highly potent, selective, and orally bioavailable CGRP receptor antagonist with Ki values of 0.77 nM and 1.2 nM for human and rhesus CGRP receptors respectively; displays >1500-fold lower affinity for the canine and rat receptors

MK-0812 is chemokine receptor CCR-2 antagonist

MK-0354 is a partial agonist of GPR109a receptor, for hGPR109a/ mGPR109a with EC50 of 1.65/1.08 μM, showed no activation of GPR109b.

Mizolastine is a histamine H1-receptor antagonist with IC50 of 47 nM used in the treatment of hay fever (seasonal allergic rhinitis), hives and other allergic reactions.

Minesapride (DSP-6952) is a novel potent, selective, orally active 5-HT4 receptor partial agonist with Ki of 50-100 nM for human 5-HT4a/4b/4c.

MF498 is a novel and selective E prostanoid receptor 4 (EP4) inhibitor, relieves joint inflammation and pain in rodent models of rheumatoid and osteoarthritis.

Metoprolol is a cardioselective β1-adrenergic blocking agent.

Mequitazine is a potent, nonsedative and long-acting histamine H1 antagonist.

Medetomidine hydrochloride is a potent and highly selective α2-AR adrenoceptor agonist (Ki values are 1.08 and 1750 nM for α2- and α1-adrenoceptors respectively). Shows greater selectivity over α1-adrenoceptors than clonidine and UK 14,304 (1620-, 220- an

Meclizine is a histamine H1 receptor antagonist used to treat nausea and motion sickness.

Maropitant is a neurokinin (NK1) receptor antagonist.

LY354740 is an agonist of the group II metabotropic glutamate receptor (mGluR) subtypes mGluR2 and mGluR3 (Kis = 99 and 94 nM, respectively).

LY344864 is a selective receptor agonist with an affinity of 6 nM (Ki) at the recently cloned 5-HT1F receptor.