Palladium black (7.00 mg, 0.0657 mmol, 1.75 eq.) was added in a single addition to (4S,4aR,5S,5aR,6R,12aS)-4-(dimethylamino)-3,5,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-1,4,4a,5,5a,6,11,12a-octahydrotetraphenyl-2- formamide (25.0 mg, 0.0375 mmol, 1.0 eq.) in a solution of tetrahydrofuran-methanol (1:1, 2.0 mL) at 23 °C. Hydrogen atmosphere was introduced by evacuating the flask and subsequently flushing it with pure hydrogen (1 atm). The palladium catalyst was initially present in a finely dispersed state but aggregated into clusters within 5 min. The yellow non-homogeneous mixture was stirred at 23°C for 2 h and then filtered through a cotton plug. The filtrate was concentrated to give a yellow oil (>95% purity based on 1H NMR analysis). The product was purified by preparative HPLC on a Phenomenex Polymerx DVB column (10 μM, 250 × 10 mm, flow rate 4.0 mL/min, solvent A: methanol-0.005N HCl aqueous solution (1:4), solvent B: acetonitrile). The product was eluted using an isochronous elution of solvent A (400 μL) containing oxalic acid (10 mg) and 5% B for 2 min, followed by a gradient of 5-50% B for 20 min. The peak eluting at 12-17 min was collected and concentrated to afford (4S,4aR,5S,5aR,6R,12aS)-4-(dimethylamino)-3,5,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-1,4,4a,5,5a,6,11,12a-octahydrotetraphenyl-2-carboxamide hydrochloride as a yellow powder ( 16.2 mg, 90% yield), and its properties were consistent with the natural product.1H NMR (600 MHz, CD3OD) δ 7.47 (t, 1H, J=8.4 Hz, ArH), 6.93 (d, 1H, J=8.4 Hz, ArH), 6.83 (d, 1H, J=8.4 Hz, ArH), 4.40 (s, 1H, (CH3) 2NCH), 3.53 (dd, 1H, J=12.0,8.4 Hz, CHOH), 2.95 (s, 3H, N(CH3)CH3'), 2.88 (s, 3H, N(CH3)CH3'), 2.80 (d, 1H, J=12.0 Hz, CHCHN(CH3)2), 2.58 (dd, 1H, J=12.6, 8.4 Hz, CH3CHCH), 1.55 (d, 3H, J=6.6 Hz, CH3CHCH); 13C NMR (100 MHz, CD3OD) δ 195.3, 188.2, 173.8, 172.1, 163.2, 149.0, 137.7, 117.1, 116.9, 116.6, 108.4, 96.0, 74.5, 69.8, 66.9, 47.5, 43.4, 43.0, 41.9, 40.0, 16.3; UV λmax (0.01N methanol HCl) 218, 267, 350 nm; [α]D = -109° (c = 0.16, 0.01 M methanol HCl); HRMS (ES) m/z calculated values ( C22H24O8N2 + H)+ 445.1611, measured value 445.1603.