**3.1 Momordicin VII (29′)**

 Several new cucurbitane triterpenoids were isolated from the stems and leaves of *M. charantia* and tested against five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW480). Only momordicin VII (**29′**) was slightly active, with IC50 values of 16.2, 20.3, 20.5, 16.9, and 14.3 μM, respectively [31].

*Structure of cucurbitane-type triterpene glycosides 15', 17'-19', 21', 24'-29'.* 

**Figure 4.**  *Structure of cucurbitane-type triterpene glycosides 20', 22', 23', 28'.* 


*Cytotoxic and Antitumoral Activities of Compounds Isolated from Cucurbitaceae Plants DOI: http://dx.doi.org/10.5772/intechopen.82213* 

#### **Table 1.**

*Cytotoxic activities of cucurbitane-type triterpene glycosides* **15′***–***28'.** 

#### **4. Multiflorane-type triterpenes**

Multiflorane-type triterpenes (**Figure 5**), a new class of cucurbitacins, were isolated from seeds of *Cucurbita maxima*, along with three known compounds from *Benincasa hispida* (Thunb.) Cogn., fruits that are widely consumed in China and tropical countries, and these compounds were found to exhibit interesting cytotoxicity activity.

 Three new multiflorane-type triterpenes, 7α-methoxymultiflor-8-ene-3α, 29-diol-3-acetate-29-benzoate (**30′**), 7-oxomultiflor-8-ene-3α,29-diol-3-acetate-29-benzoate (**31′**), and multiflora-7,9(11)-diene-3α,29-diol-3-p-hydroxybenzoate-29 benzoate (**32′**), were isolated from seeds of *C. maxima*, along with three known compounds. These compounds exhibited cytotoxicity against HL-60 and P388 cells. Compound (**30′**) did not show significant cytotoxic activity, with an IC50 > 100 μM in both lines, but compounds 31 and 32 showed cytotoxic activity against HL-60, with IC50 values of 7.1 and 7.1 μM, respectively. The IC50 values for P388 were 55.9 and 92.6 μM, respectively [32].

Analysis of *Benincasa hispida* (Thunb.) Cogn. fruits yielded three new triterpenoids, 3α,29-O-di-trans-cinnamoyl-D:C-friedooleana-7,9(11)-diene (**33′**), oleanolic acid 28-O-β-D-xylopyranosyl-[β-D-xylopyranosyl-(1→4)]-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (**34′**), and oleanolic acid 28-O-β-D-glucopyranosyl-(1→3)-β-D-xylopyranosyl-[β-D-xylopyranosyl-

**Figure 5.** 

*Multiflorane-type triterpenes.* 

(1→4)]-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (**35′**). The cytotoxic activities of compounds (**33′−35′**) were assessed by the MTT assay. These compounds showed no significant cytotoxic activity against HeLa human cervical, HL-60 human hepatoma, and SMMC-7721 human hepatoma cell lines [33].
