▎ 摘　　要

NOVELTY - An indole-containing compound (I), is new. USE - New compound (I) used as imaging agent for detecting cancer such as blastoma, carcinoma, glioma, leukemia, lymphoma, melanoma, myeloma, sarcoma, head cancer, neck cancer, head and neck cancer, lung cancer, breast cancer, triple negative breast cancer, prostate cancer, colorectal cancer, esophageal cancer, stomach cancer, leukemia/lymphoma, uterine cancer, skin cancer, endocrine cancer, urinary cancer, pancreatic cancer, gastrointestinal cancer, ovarian cancer, cervical cancer, renal cancer, bladder cancer, brain cancer, adenoma, and metastatic cancer, solid tumor in organ such as brain, colon, breast, prostate, liver, kidney, lung, esophagus, head and neck, ovary, cervix, stomach, rectum, bladder, uterus, testes, and pancreas, microbial infection due to microorganisms such as Mycobacterium tuberculosis, E. coli, Klebsiella sp., Enterobacter sp., Proteus sp., Serratia marcescens, Pseudomonas aeruginosa, Staphylococcus spp., including S. aureus and coagulase-negative Staphylococcus, Enterococcus sp., Streptococcus pneumoniae, Haemophilus influenzae, Bacteroides spp., Acinetobacter spp., Helicobacter spp., Candida sp., methicillin-resistant S. aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VRE), inflammation related to a disorder such as asthma, autoimmune disease, autoinflammatory disease, Celiac disease, diverticulitis, glomerulonephritis, hidradenitis suppurativa, hypersensitivity, inflammatory bowel disease, interstitial cystitis, otitis, pelvic inflammatory disease, reperfusion injury, rheumatic fever, rheumatoid arthritis, sarcoidosis, transplant rejection, lupus, systemic lupus erythematosus, and vasculitis, immune cells in a tumor, systemic distribution of immune cells in tumor or in subject, immune cell response to infectious disease, and programmed death-ligand 1 expression levels in subject such as human, rat, mouse, cat, dog, horse, sheep, cow, monkey, avian, or amphibian (all claimed). ADVANTAGE - The compound (I) has excellent PD-L1 inhibiting activity, and efficacy. DETAILED DESCRIPTION - An indole-containing compound of formula (I), is new. L = optionally linker of formula (a); X = S or O; a,e,f,g,i,j = 0 and 1; b,d,h,k = 0-8; c = 0-40; R1 = H or -COOR2; R2 = H or 1-4C alkyl; Ar' = optionally substituted aryl or heteroaryl; A = reporting moiety chosen from chelating agent, a radiolabeled substrate, a fluorescent dye, a photoacoustic reporting molecule, and a Raman-active reporting molecule or an end group chosen from groups of formulae: -NR3R4 or CN;and R3,R4 = H or 1-4C alkyl. INDEPENDENT CLAIMS are included for the following: (1) detection of programmed death ligand 1 (PD-L1), which involves providing an effective amount of an imaging agent, contacting cells or tissues with the imaging agent, and making an image to detect PD-L1; and (2) PD-L1 detecting kit, which comprises the compound (I).