*Article* **Unusual Polyhydroxylated Steroids from the Starfish** *Anthenoides laevigatus***, Collected o**ff **the Coastal Waters of Vietnam**

**Alla A. Kicha 1,\*, Dinh T. Ha 2,3, Timofey V. Malyarenko 1,4, Anatoly I. Kalinovsky 1, Roman S. Popov 1, Olesya S. Malyarenko 1, Tran T. T. Thuy 3,\*, Pham Q. Long 3, Nguyen T. T. Ha <sup>5</sup> and Natalia V. Ivanchina <sup>1</sup>**


Academic Editor: Pavel S. Dmitrenok Received: 13 February 2020; Accepted: 20 March 2020; Published: 23 March 2020

**Abstract:** Four new polyhydroxylated steroids **1**–**4** were isolated along with two previously known related steroids **5** and **6** from the methanolic extract of the starfish *Anthenoides laevigatus* collected off the coastal waters of Vietnam. Structures of new compounds were substantially elucidated by one-dimensional (1D) and two-dimensional (2D) NMR spectroscopy and HRESIMS techniques. Heptaol **1** and hexaol **2** contain the common 5α-cholestane skeleton, while hexaol **3** and heptaol **4** have the rare among starfish steroid compounds 5β-cholestane skeleton. Compounds **1**, **5**, and **6** do not show cytotoxic effects against normal JB6 Cl41 and cancer HT-29 and MDA-MB-231 cells, however they inhibit cell proliferation and colony formation of cancer HT-29 and MDA-MB-231 cells.

**Keywords:** polyhydroxylated steroids; NMR spectra; starfish; *Anthenoides laevigatus*; cytotoxicity; soft agar assay
