Task: Class Definition Understanding (ontology: Sciences/Biology)

Which of the following definitions best describes 'isoindolin-1-one'?

A. A member of the class of isoindoles that is 2,3-dihydro-1H-isoindole in which the hydrogens at positon 1 are replaced by an oxo group.
B. A member of the class of isoindoles that is 1H-isoindole-1,3(2H)-dione substituted at position 5 by a 4-bromoanilinocarbonyl group and at position 2 by a 4-[(4-bromophenyl)carbamoyl]phenyl group.
C. A member of the class of isoindoles that is isoindole in which the amino group has been acylated by a 2,4-dihydroxy-5-isopropylbenzoyl group and in which position 5 of the isoidole moiety has been substituted by a (4-methylpiperazin-1-yl)methyl group. A second-generation Hsp90 inhibitor.
D. An organic heterooctacyclic compound that is the N-benzoyl derivative of staurosporine.

Answer: A member of the class of isoindoles that is 2,3-dihydro-1H-isoindole in which the hydrogens at positon 1 are replaced by an oxo group.