1,464 research outputs found

    3,3′-Dibromo-5,5′-bis­[(S)-l-menth­yloxy]-4,4′-(hexane-1,6-diyldiimino)difuran-2(5H)-one

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    The title compound, C34H54Br2N2O6, was obtained by the Michael addition–elimination reaction of (5S)-5-(l-menthyl­oxy)-3,4-dibromo­furan-2(5H)-one with 1,6-hexa­nediamine in the presence of triethyl­amine. The crystal structure contains two chiral five-membered furan­one rings, in twist and envelope conformations, and two six-membered cyclo­hexane rings in chair conformations

    N-[(2S)-4-Chloro-2-(l-menth­yloxy)-5-oxo-2,5-dihydro­furan-3-yl]-l-valine

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    The title compound, C19H30ClNO5, was obtained by the tandem asymmetric Michael addition–elimination reaction of (5S)-3,4-dichloro-5-(l-menth­yloxy)furan-2(5H)-one and l-valine in the presence of potassium hydroxide. The furan­one unit is approximately planar (r.m.s. deviation = 0.0204 Å) and the six-membered cyclo­hexane ring adopts a chair conformation. The crystal structure is stabilized by a network of O—H⋯O and N—H⋯O hydrogen bonds

    GPT4Tools: Teaching Large Language Model to Use Tools via Self-instruction

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    This paper aims to efficiently enable Large Language Models (LLMs) to use multimodal tools. Advanced proprietary LLMs, such as ChatGPT and GPT-4, have shown great potential for tool usage through sophisticated prompt engineering. Nevertheless, these models typically rely on prohibitive computational costs and publicly inaccessible data. To address these challenges, we propose the GPT4Tools based on self-instruct to enable open-source LLMs, such as LLaMA and OPT, to use tools. It generates an instruction-following dataset by prompting an advanced teacher with various multi-modal contexts. By using the Low-Rank Adaptation (LoRA) optimization, our approach facilitates the open-source LLMs to solve a range of visual problems, including visual comprehension and image generation. Moreover, we provide a benchmark to evaluate the ability of LLMs to use tools, which is performed in both zero-shot and fine-tuning ways. Extensive experiments demonstrate the effectiveness of our method on various language models, which not only significantly improves the accuracy of invoking seen tools, but also enables the zero-shot capacity for unseen tools. The code and demo are available at https://github.com/StevenGrove/GPT4Tools

    A New Epoxy-cadinane Sesquiterpene from the Marine Brown Alga Dictyopteris divaricata

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    A new epoxy-cadinane sesquiterpene, 4β,5β-epoxycadinan-1β-ol (1), and six known cadinane sesquiterpenes: cadinan-1,4,5-triol (2), 4α,5β-dihydroxycubenol (3), cubenol (4), cadinan-3-ene-1,5-diol (5), cubenol-3-one (6), and torreyol (7), were isolated from a sample of marine brown alga Dictyopteris divaricata collected off the coast of Yantai (China). Their structures were established by detailed MS and NMR spectroscopic analysis, as well as comparison with literature data

    N-[(2S)-4-Chloro-2-(l-menthyloxy)-5-oxo-2,5-dihydro-3-furyl]-l-alanine

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    The title compound, C17H26ClNO5, was prepared via a tandem asymmetric Michael addition–elimination reaction of (5S)-3,4-dichloro-5-(l-menth­yloxy)furan-2(5H)-­one and l-alanine in the presence of potassium hydroxide. The five-membered furan­one ring is approximately planar while the six-membered menth­yloxy ring adopts a chair conformation. The crystal packing is stabilized by inter­molecular O—H⋯O and N—H⋯O hydrogen bonds

    Poly[[aqua­(μ5-1H-benzimidazole-5,6-dicarboxyl­ato)(μ4-1H-benzimidazole-5,6-dicarboxyl­ato)dibarium] 4.5-hydrate]

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    The polymeric title compound, {[Ba2(C9H4N2O4)2(H2O)]·4.5H2O}n, adopts a layer structure parallel to (001) in which adjacent BaII atoms are connected by two benzimidazole-5,6-dicarboxyl­ate dianions, one functioning in a μ4-bridging mode and the other in a μ5-bridging mode. The Ba atom having water in its coordination environment as well as the Ba atom without water exist in a nine-coordinate polyhedron of O atoms; the geometry is difficult to derive. Lattice water mol­ecules occupy the space between layers and inter­act with the layers through O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds. ne of the five lattice water molecules is equally disordered around an inversion centre and shows half-occupancy
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