Derivatives of steroids with condensed heterocycles

CONTENTS
I. Introduction 311
II. Five-membered heterocycles with one heteroatom 312
III. Five-membered heterocycles with two heteroatoms 314
IV. Five-membered heterocycles with three heteroatoms 319
V. Six-membered heterocycles with one heteroatom 320
VI. Six-membered heterocycles with two heteroatoms 320
VII. Condensed heterocyclic systems with several heteroatoms 322