464-43-7Relevant articles and documents
Simple Plug-In Synthetic Step for the Synthesis of (?)-Camphor from Renewable Starting Materials
Calderini, Elia,Drienovská, Ivana,Myrtollari, Kamela,Pressnig, Michaela,Sieber, Volker,Schwab, Helmut,Hofer, Michael,Kourist, Robert
, p. 2951 - 2956 (2021/06/18)
Racemic camphor and isoborneol are readily available as industrial side products, whereas (1R)-camphor is available from natural sources. Optically pure (1S)-camphor, however, is much more difficult to obtain. The synthesis of racemic camphor from α-pinene proceeds via an intermediary racemic isobornyl ester, which is then hydrolyzed and oxidized to give camphor. We reasoned that enantioselective hydrolysis of isobornyl esters would give facile access to optically pure isoborneol and camphor isomers, respectively. While screening of a set of commercial lipases and esterases in the kinetic resolution of racemic monoterpenols did not lead to the identification of any enantioselective enzymes, the cephalosporin Esterase B from Burkholderia gladioli (EstB) and Esterase C (EstC) from Rhodococcus rhodochrous showed outstanding enantioselectivity (E>100) towards the butyryl esters of isoborneol, borneol and fenchol. The enantioselectivity was higher with increasing chain length of the acyl moiety of the substrate. The kinetic resolution of isobornyl butyrate can be easily integrated into the production of camphor from α-pinene and thus allows the facile synthesis of optically pure monoterpenols from a renewable side-product.
Enantioselective Construction of Modular and Asymmetric Baskets
Badji?, Jovica D.,Finnegan, Tyler J.,Gunther, Michael J.,Pavlovi?, Radoslav Z.,Wang, Xiuze
supporting information, p. 25075 - 25081 (2021/10/25)
The precise positioning of functional groups about the inner space of abiotic hosts is a challenging task and of interest for developing more effective receptors and catalysts akin to those found in nature. To address it, we herein report a synthetic methodology for preparing basket-like cavitands comprised of three different aromatics as side arms with orthogonal esters at the rim for further functionalization. First, enantioenriched A (borochloronorbornene), B (iodobromonorbornene), and C (boronorbornene) building blocks were obtained by stereoselective syntheses. Second, consecutive A-to-B and then AB-to-C Suzuki–Miyaura (SM) couplings were optimized to give enantioenriched ABC cavitand as the principal product. The robust synthetic protocol allowed us to prepare (a) an enantioenriched basket with three benzene sides and each holding either tBu, Et, or Me esters, (b) both enantiomers of a so-called “spiral staircase” basket with benzene, naphthalene, and anthracene groups surrounding the inner space, and (c) a photo-responsive basket bearing one anthracene and two benzene arms.
Molecular cloning and functional characterization of a two highly stereoselective borneol dehydrogenases from Salvia officinalis L
Drienovská, Ivana,Kolanovi?, Dajana,Chánique, Andrea,Sieber, Volker,Hofer, Michael,Kourist, Robert
, (2020/01/11)
Enzymes for selective terpene functionalization are of particular importance for industrial applications. Pure enantiomers of borneol and isoborneol are fragrant constituents of several essential oils and find frequent application in cosmetics and therapy. Racemic borneol can be easily obtained from racemic camphor, which in turn is readily available from industrial side-streams. Enantioselective biocatalysts for the selective conversion of borneol and isoborneol stereoisomers would be therefore highly desirable for their catalytic separation under mild reaction conditions. Although several borneol dehydrogenases from plants and bacteria have been reported, none show sufficient stereoselectivity. Despite Croteau et al. describing sage leaves to specifically oxidize one borneol enantiomer in the late 70s, no specific enzymes have been characterized. We expected that one or several alcohol dehydrogenases encoded in the recently elucidated genome of Salvia officinalis L. would, therefore, be stereoselective. This study thus reports the recombinant expression in E. coli and characterization of two enantiospecific enzymes from the Salvia officinalis L. genome, SoBDH1 and SoBDH2, and their comparison to other known ADHs. Both enzymes produce preferentially (+)-camphor from racemic borneol, but (?)-camphor from racemic isoborneol.
Monoterpenoid-based inhibitors of filoviruses targeting the glycoprotein-mediated entry process
Baev, Dmitriy S.,Maksyutov, Rinat A.,Mordvinova, Ekaterina D.,Pyankov, Oleg V.,Salakhutdinov, Nariman F.,Shcherbakov, Dmitriy N.,Shcherbakova, Nadezhda S.,Sokolova, Anastasiya S.,Tolstikova, Tatyana G.,Yarovaya, Olga I.,Zaykovskaya, Anna V.,Zybkina, Anastasiya V.
, (2020/09/09)
In this study, we screened a large library of (+)-camphor and (?)-borneol derivatives to assess their filovirus entry inhibition activities using pseudotype systems. Structure-activity relationship studies revealed several compounds exhibiting submicromolar IC50 values. These compounds were evaluated for their effect against natural Ebola virus (EBOV) and Marburg virus. Compound 3b (As-358) exhibited the good antiviral potency (IC50 = 3.7 μM, SI = 118) against Marburg virus, while the hydrochloride salt of this compound 3b·HCl had a strong inhibitory effect against Ebola virus (IC50 = 9.1 μM, SI = 31) and good in vivo safety (LD50 > 1000 mg/kg). The results of molecular docking and in vitro mutagenesis analyses suggest that the synthesized compounds bind to the active binding site of EBOV glycoprotein similar to the known inhibitor toremifene.
Direct Reductive Amination of Camphor Using Iron Pentacarbonyl as Stoichiometric Reducing Agent: Features and Limitations
Afanasyev, Oleg I.,Amangeldyev, Artem,Chusov, Denis,Fatkulin, Artemy R.,Semenov, Sergey E.,Smirnov, Ivan,Solyev, Pavel N.
supporting information, p. 6289 - 6294 (2020/10/06)
The method of direct reductive amination of camphor and fenchone was proposed. The most effective reducing agent is iron carbonyl. No ligands or solvents are needed. The stereochemistry of the corresponding products was determined by HMBC, HSQC, and NOESY
Aryl borate derivative of 2-borneol and application thereof
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Paragraph 0034-0037, (2019/01/20)
The invention relates to an aryl borate derivative of 2-borneol and an application thereof. The structural formula is shown as formula (I), wherein R1 and R2 are alkyl groups and can be connected intoan annular structure. Such a compound is sensitive to i
Flat and Efficient H CNN and CNN Pincer Ruthenium Catalysts for Carbonyl Compound Reduction
Giboulot, Steven,Baldino, Salvatore,Ballico, Maurizio,Figliolia, Rosario,P?thig, Alexander,Zhang, Shuanming,Zuccaccia, Daniele,Baratta, Walter
, p. 1127 - 1142 (2019/03/14)
The bidentate HCNN dicarbonyl ruthenium complexes trans,cis-[RuCl2(HCNN)(CO)2] (1-3) and trans,cis-[RuCl2(ampy)(CO)2] (1a) were prepared by reaction of [RuCl2(CO)2]n with 1-[6-(4′-methylphenyl)pyridin-2-yl]methanamine, benzo[h]quinoline (HCNN), and 2-(aminomethyl)pyridine (ampy) ligands. Alternatively, the derivatives 1-3 were obtained from the reaction of RuCl3 hydrate with HCO2H and HCNN. The pincer CNN cis-[RuCl(CNN)(CO)2] (4) was isolated from 1 by reaction with NEt3. The monocarbonyl complexes trans-[RuCl2(HCNN)(PPh3)(CO)] (5-7) were synthesized from [RuCl2(dmf)(PPh3)2(CO)] and HCNN ligands, while the diacetate trans-[Ru(OAc)2(HCNN)(PPh3)(CO)] (8) was obtained from [Ru(OAc)2(PPh3)2(CO)]. Carbonylation of cis-[RuCl(CNN)(PPh3)2] with CO afforded the pincer derivatives [RuCl(CNN)(PPh3)(CO)] (9-11). Treatment of 9 with Na[BArf]4 and PPh3 gave the cationic complex trans-[Ru(CNN)(PPh3)2(CO)][BArf4] (12). The dicarbonyl derivatives 1-4, in the presence of PPh3 or PCy3, and the monocarbonyl complexes 5-12 catalyzed the transfer hydrogenation (TH) of acetophenone (a) in 2-propanol at reflux (S/C = 1000-100000 and TOF up to 100000 h-1). Compounds 1-3, with PCy3, and 6 and 8-10 were proven to catalyze the TH of carbonyl compounds, including α,β-unsaturated aldehydes and bulky ketones (S/C and TOF up to 10000 and 100000 h-1, respectively). The derivatives 1-3 with PCy3 and 5 and 6 catalyzed the hydrogenation (HY) of a (H2, 30 bar) at 70 °C (S/C = 2000-10000). Complex 5 was active in the HY of diaryl ketones and aryl methyl ketones, leading to complete conversion at S/C = 10000.
Hydrogen Sulfide: A Reagent for pH-Driven Bioinspired 1,2-Diol Mono-deoxygenation and Carbonyl Reduction in Water
Barata-Vallejo, Sebastián,Ferreri, Carla,Golding, Bernard T.,Chatgilialoglu, Chryssostomos
supporting information, p. 4290 - 4294 (2018/07/29)
Hydrogen sulfide (H2S) was evaluated for its peculiar sulfur radical species generated at different pHs and was used under photolytical conditions in aqueous medium for the reduction of 1,2-diols to alcohols. The conversion steps of 1,2-cyclopentanediol to cyclopentanol via cyclopentanone were analyzed, and it was proven that the reaction proceeds via a dual catalytic/radical chain mechanism. This approach was successfully adapted to the reduction of a variety of carbonyl compounds using H2S at pH 9 in water. This work opens up the field of environmental friendly synthetic processes using the pH-driven modulation of reactivity of this simple reagent in water.
Reliably Regioselective Dialkyl Ether Cleavage with Mixed Boron Trihalides
Atienza, Bren Jordan P.,Truong, Nam,Williams, Florence J.
supporting information, p. 6332 - 6335 (2018/10/09)
A protocol for the regioselective cleavage of unsymmetrical alkyl ethers to generate alkyl alcohol and alkyl bromide products is described. A mixture of trihaloboranes triggers this conversion and exhibits improved reactivity profiles (regioselectivity and yield) compared with BBr3 alone. Additionally, this procedure allows the efficient synthesis of (B-Cl) dialkyl boronate esters. There are limited methods to generate acyclic dialkoxyboryl chlorides, and these intermediates constitute important synthons in main-group chemistry.
Preparation method of D-borneol
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Paragraph 0032; 0033; 0037; 0042; 0046, (2018/11/22)
The invention relates to a preparation method of D-borneol. The method comprises the following steps: ensuring that natural camphor is reacted for 1 to 8 hours at 0 to 40 DEG C under the existence ofan organic solvent and a chiral reagent (R)-BINAP-H serving as catalysts, and ensuring that the optimized ratio of the organic solvent to the chiral reagent (R)-BINAP-H to camphor is (10-30ml): (20-50mmol): 18mmol.
