Table 1.

Physical properties and ¹H-NMR data of marrubiin [31].

Physical properties	Value	NMR data [37]
Molecular weight	332.43	* Overlapped signals
Molecular formula	C20 H28 O4
CAS Registry Number	465-92-9
Molar volume	288 ± 3.0 cm3/mol(20 °C; 760 Torr)
Density	1.152±0.06 g/cm3(20 °C; 760 Torr)
Melting Point	~155–160 °C
Freely Rotatable Bonds	4
H Acceptors	4
H Donors	1
H Donor/ Acceptor sum	5
LogP	3.796±0.414 (at 25 °C)
[α]D:	+45.68° (acetone, 24 °C), +35.8 (CHCl3, 24 °C)