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A catalytic asymmetric vinylogous aldol reaction between β,γ-unsaturated amides and isatins has been developed. In the presence of 10 mol% of tertiary amine-thiourea C7, the vinylogous reaction has been achieved in up to 98% yield and up to 99% ee (26 examples). This methodology provides an efficient approach to construct chiral multifunctional 3-hydroxy-2-oxindoles. Moreover, the transformations of the chiral products, including the esterification of amides, the hydrogenation of the C–C double bond and further conversion to spirolactones, have been investigated. [ABSTRACT FROM AUTHOR]

Six new triterpenes, 3β,6β-dihydroxyurs-12-en-27-oic acid (1), 3β,6β,24-trihydroxyurs-12-en-27-oic acid (2), 3β,6β,7α-trihydroxyurs-12-en-27-oic acid (3), 3β-acetoxy-6β-hydroxyurs-12-en-27-oic acid (4), 3β,6β,24-trihydroxyolean-12-en-27-oic acid (5), and 3β,6β,7α-trihydroxyolean-12-en-27-oic acid (6), were isolated from the rhizomes of Astilbe chinensis. Their structures were elucidated on the basis of 1D- and 2D-NMR analyses and HR-MS experiments. The isolated compounds exhibited significant cytotoxic activities against the SK-N-SH and HL-60 cell lines. [ABSTRACT FROM AUTHOR]

The dried stems of Schisandra henryi var. henryi were extracted with 95% ethanol and the extracts were further subjected to partition, affording the ethyl acetate extracts(EtOAc Extrs.).The EtOAc Extrs.were separated and purified with silica gel and octadecyl-silylated silica gel column chromatography, preparative HPLC and preparative TLC. Thirteen known compounds were obtained and identified by spectral methods including MS and NMR, all of which were elucidated as t-cadinol(1), cadinane-4β,5α,10β-triol(2), cadinane-5α, 10α-diol-2-ene(3), oxyphyllenodiols A(4), 1β, 4β-dihydroxyeudesman-11-ene(5), cyperusol C(6), (7R)-opposit-4(15)-ene-1β,7-diol(7), dysodensiol E(8), epi-guaidiol A(9), aromadendrane-4β,10β-diol(10), tricyclohumuladiol(11), caryolane-1,9β-diol(12), and guaidiol A(13). Compounds 3, 5-10, and 13 were separated from the genus for the first time, while compounds 1-13 were separated from this species for the first time., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Based on the life cycle cost (LCC) approach, this paper presents an integral mathematical model and particle swarm optimization (PSO) algorithm for the heating system planning (HSP) problem. The proposed mathematical model minimizes the cost of heating system as the objective for a given life cycle time. For the particularity of HSP problem, the general particle swarm optimization algorithm was improved. An actual case study was calculated to check its feasibility in practical use. The results show that the improved particle swarm optimization (IPSO) algorithm can more preferably solve the HSP problem than PSO algorithm. Moreover, the results also present the potential to provide useful information when making decisions in the practical planning process. Therefore, it is believed that if this approach is applied correctly and in combination with other elements, it can become a powerful and effective optimization tool for HSP problem.

In the pregnene fragment of the title compound, C27H38ClN, the three six-membered rings exhibit chair conformations and the five-membered ring has a distorted envelope form with the fused C atom not bearing a methyl group as the flap atom. The amino group is involved in the formation of an intra-molecular N-H⋯Cl hydrogen bond. The crystal packing exhibits no short inter-molecular contacts.

There are two independent mol-ecules in the asymmetric unit of the title compound, C(30)H(44)O(5). They comprise a triterpenoid skeleton of five six-membered rings and a five-membered lactone ring. The five six-membered rings are all trans-fused. In both independent mol-ecules the D rings adopt a slightly distorted half-chair conformation due the presence of the lactone ring while the other four six-membered rings all adopt chair conformations. The characteristic carbon-carbon double bond of the oleanoic skeleton is absent. Inter-molecular O-H⋯O hydrogen bonds between the hy-droxy and carbonyl groups occur in the crystal structure.

The mol-ecule of title compound, C(39)H(56)O(5), contains five fused six-membered rings, four of which (rings A, B, D and E) adopt a chair conformation, while the other (ring C) has a half chair conformation. The acet-oxy and carb-oxy-benzyl groups occupy equatorial positions.