| Azirines | Unsaturated azacyclopropane compounds that are three-membered heterocycles of a nitroge... more | 14 | 21 | Details |
| Azo Compounds | Organic chemicals where aryl or alkyl groups are joined by two nitrogen atoms through a... more | 5 | 14 | Details |
| Azocines | Not Available | 3 | 8 | Details |
| Azole Antifungals | Not Available | 28 | 199 | Details |
| B Lymphocyte Stimulator-directed Antibody Interactions | Not Available | 1 | 1 | Details |
| B Lymphocyte Stimulator-specific Inhibitor | Not Available | 2 | 3 | Details |
| B-Cell Activating Factor | Not Available | 1 | 1 | Details |
| B-Cell Activating Factor, antagonists & inhibitors | Not Available | 1 | 1 | Details |
| B-Raf serine-threonine kinase (BRAF) inhibitors | Not Available | 4 | 71 | Details |
| Bacitracins | Not Available | 1 | 6 | Details |
| Bacteria | Not Available | 1 | 2 | Details |
| Bacterial and viral vaccines, combined | Not Available | 1 | 0 | Details |
| Bacterial Neurotoxin Neutralization | Not Available | 1 | 0 | Details |
| Bacterial Proteins | Proteins found in any species of bacterium. | 12 | 21 | Details |
| Bacterial Toxins | Toxic substances formed in or elaborated by bacteria; they are usually proteins with hi... more | 19 | 26 | Details |
| Bacterial Vaccines | Suspensions of attenuated or killed bacteria administered for the prevention or treatme... more | 11 | 0 | Details |
| Bactericidal permeability increasing polypeptide | Not Available | 0 | 0 | Details |
| Bacteriochlorophylls | Pyrrole containing pigments found in photosynthetic bacteria. | 1 | 2 | Details |
| Bacteriocins | Substances elaborated by specific strains of bacteria that are lethal against other str... more | 1 | 0 | Details |
| Baloxavir and prodrugs | Not Available | 2 | 8 | Details |
| Bandages | Not Available | 0 | 0 | Details |
| Barbiturates | A class of chemicals derived from barbituric acid or thiobarbituric acid. Many of these... more | 16 | 173 | Details |
| Barbiturates and Derivatives | Not Available | 5 | 72 | Details |
| Barbiturates, Plain | Not Available | 17 | 127 | Details |
| Barium Compounds | Inorganic compounds that contain barium as an integral part of the molecule. | 1 | 1 | Details |