Table schema:
CREATE TABLE table_12715053_1 (compound_name VARCHAR, chemical_class VARCHAR, clinical_trials_β VARCHAR)

Question: How many compound names list a chemical class of depsipeptide and a clinical trials β value of 1/7?
SQL: SELECT COUNT(compound_name) FROM table_12715053_1 WHERE chemical_class = "Depsipeptide" AND clinical_trials_β = "1/7"