Synthesis of tunichrome Sp-1

Marine natural products

“…The structure of tunichrome Sp-1 (ref. 943) has been conrmed by total synthesis 944 and a new catalytic asymmetric synthetic route to (À)-perophoramidine 945 has been disclosed. 946 Cell-cycle arrest at the G 2 /M phase and induction of apoptosis in HeLa cells 947 was observed for the ascidian alkaloid eudistomin H, 948 while eusynstyelamide B 949 also induces G 2 /M phase arrest, causes double strand breaks in DNA and is a topisomerase II poison.…”

Synthesis and biological evaluation of the ascidian blood-pigment halocyamine A

“…R f 0.48 (n-hexane/EtOAc 7 : 3); IR (ATR) ν max 3333,2977,1674,1512,1453,1368, 1252 cm −1 ; 1 H NMR (CDCl 3 , 400 MHz) δ 8.42 (1H, d, J = 10.4 Hz, NH-4), 7.37 (2H, t, J = 7.7 Hz, 2H-9), 7.27 (2H, d, J = 7.7 Hz, 2H-8), 7.24-7.22 (1H, m, H-10), 6.93 (1H, dd, J = 10.4, 9. 7 (Z)-2-Amino-N-styrylacetamide (8). A solution of piperidine (0.9 mL, 20% in DMF) was added to 10 (0.086 g, 0.22 mmol) and stirred under nitrogen for 20 min.…”

“…Biological evaluation of halocyamine A revealed a wide range of activities, including growth inhibition of Gram-positive bacteria, 4a Gram-negative marine bacteria and fish RNA viruses. 7 As part of our ongoing investigation of the synthesis and biological investigation of tunichromes, 8 we now report the synthesis and structural confirmation of halocyamine A (1) and present the results of preliminary biological evaluation.…”