The Trendione, with the CAS registry number 4642-95-9, is also known as (8S,13R,14S)-13-Methyl-1,2,6,7,8,14,15,16-octahydrocyclopenta[a]phenanthrene-3,17-dione. This chemical's molecular formula is C₁₈H₂₀O₂ and molecular weight is 268.35. What's more, its systematic name is Estra-4,9,11-triene-3,17-dione. 

Physical properties of Trendione are: (1)ACD/LogP: 2.378; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 2.38; (4)ACD/LogD (pH 7.4): 2.38; (5)ACD/BCF (pH 5.5): 37.76; (6)ACD/BCF (pH 7.4): 37.76; (7)ACD/KOC (pH 5.5): 468.21; (8)ACD/KOC (pH 7.4): 468.21; (9)#H bond acceptors: 2; (10)#H bond donors: 0; (11)#Freely Rotating Bonds: 0; (12)Polar Surface Area: 34.14 Å²; (13)Index of Refraction: 1.595; (14)Molar Refractivity: 76.465 cm³; (15)Molar Volume: 224.986 cm³; (16)Polarizability: 30.313×10^-24cm³; (17)Surface Tension: 46.42 dyne/cm; (18)Density: 1.193 g/cm³; (19)Flash Point: 181.316 °C; (20)Enthalpy of Vaporization: 75.571 kJ/mol; (21)Boiling Point: 489.403 °C at 760 mmHg; (22)Vapour Pressure: 0 mmHg at 25°C.

Preparation of Trendione: this chemical can be prepared by 1,1,1-triethoxy-ethane and 11b-hydroxyestr-4,10-diene-3,17-dione at the temperature of 137 °C. This reaction will need solvent propionic acid with the reaction time of 4 hours. The yield is about 81%.

You can still convert the following datas into molecular structure:
(1)SMILES: O=C4\C=C3/C(=C2/C=C\[C@@]1(C(=O)CC[C@H]1[C@@H]2CC3)C)CC4
(2)Std. InChI: InChI=1S/C18H20O2/c1-18-9-8-14-13-5-3-12(19)10-11(13)2-4-15(14)16(18)6-7-17(18)20/h8-10,15-16H,2-7H2,1H3/t15-,16+,18+/m1/s1
(3)Std. InChIKey: KBSXJBBFQODDTQ-RYRKJORJSA-N