Isoxazole
                            Order
                            25043-13-4
                            
                                6H,7H-Cyclopenta[7,8]cyclopropa[4a,4b]phenanthro[2,1-c]isoxazole,9,19-cyclopregnano[3,4-c]isoxazole deriv.
                            
                        
                        
                        
                        
                            Order
                            65981-17-1
                            
                                Cyclopenta[7,8]phenanthro[10,1-cd]isoxazole,cholest-4-eno[6,5,4-cd]isoxazole deriv.