The CAS register number of 2H-Pyran-2-one,5,6-dihydro-6-pentyl-, (6R)- is 51154-96-2. It also can be called as Massoia lactone and the systematic name about this chemical is (6R)-6-pentyl-5,6-dihydro-2H-pyran-2-one. The molecular formula about this chemical is C₁₀H₁₆O₂ and the molecular weight is 168.23284.

Physical properties about 2H-Pyran-2-one,5,6-dihydro-6-pentyl-, (6R)- are: (1)ACD/LogP: 2.54; (2)ACD/LogD (pH 5.5): 2.54; (3)ACD/LogD (pH 7.4): 2.54; (4)ACD/BCF (pH 5.5): 50.16; (5)ACD/BCF (pH 7.4): 50.16; (6)ACD/KOC (pH 5.5): 573.79; (7)ACD/KOC (pH 7.4): 573.79; (8)#H bond acceptors: 2; (9)#Freely Rotating Bonds: 4; (10)Polar Surface Area: 26.3 Å²; (11)Index of Refraction: 1.458; (12)Molar Refractivity: 47.62 cm³; (13)Molar Volume: 174.3 cm³; (14)Polarizability: 18.87x10^-24cm³; (15)Surface Tension: 31.1 dyne/cm; (16)Density: 0.964 g/cm³; (17)Flash Point: 115.8 °C; (18)Enthalpy of Vaporization: 52.62 kJ/mol; (19)Boiling Point: 287 °C at 760 mmHg; (20)Vapour Pressure: 0.00254 mmHg at 25 °C.

This chemical  used as a natural coconut flavouring, natural massoia lactone has been largely superseded by a synthetic alternative because the extraction process is expensive and the tree is killed during the process of removing the bark. It has an odour that is described as sweet, coconut meat, lactonic, creamy, milky and waxy and, at a dilution of 20 ppm, a taste described as creamy, coconut, green and slightly fruity.

You can still convert the following datas into molecular structure:
(1)SMILES: O=C\1O[C@H](CCCCC)C/C=C/1
(2)InChI: InChI=1/C10H16O2/c1-2-3-4-6-9-7-5-8-10(11)12-9/h5,8-9H,2-4,6-7H2,1H3/t9-/m1/s1
(3)InChIKey: NEDIAPMWNCQWNW-SECBINFHBH
(4)Std. InChI: InChI=1S/C10H16O2/c1-2-3-4-6-9-7-5-8-10(11)12-9/h5,8-9H,2-4,6-7H2,1H3/t9-/m1/s1
(5)Std. InChIKey: NEDIAPMWNCQWNW-SECBINFHSA-N