この研究は、(文部) 日本の科学省からの補助金によって融資された (番 15 K 00408、24659011、24640156、245900425、新青木の 22390005)、東京の生化学的研究からの助成金で財団、東京都、東京理科大学 (東京理科大学) 基金の戦略的研究分野。感謝澤邊紀子 (薬学部、東京理科大学) 長谷川富貴子 (薬学部、東京理科大学) の NMR スペクトルの測定質量の測定したいと思いますスペクトル、および元素分析測定のため朋子松尾 (東京理科大学理工学研究所)。

著者が明らかに何もありません。

本稿の目的は、退屈な保護グループ操作することがなく保護されていない ribonucleosides を用いた糖ヌクレオシドの準備に便利な合成法を示すことです。ここのヌクレオシドを介して、一時 2', 3'-ジオール保護繰返しホウ酸エステル (図 1B)51 O位置選択的グリコシル化について報告する.
中間周期のホウ酸エステルの準備は、重要な手順の 1 つです。無水溶媒される反応混合物 (手順 1.1.1.2 とプロトコルの 1.2.1.1.2) の蒸着、エステル化ステップ (手順 1.1.1.3 および 1.2.1.1.3) ヌクレオシドとボロン酸から調製したホウ酸エステルの可能性がありますので容易に加水分解します。O- グリコシル化反応には、糖供与の加水分解を避けるために無水条件も必要です。したがって、分子ふるい (手順 1.1.2 および 1.2.1.2)、2 首丸底フラスコ、無水溶媒 (手順 1.1.3.1 と 1.2.1.3.1) は、 O糖のため、使用前に十分に乾燥されてする必要があります。
-20 ° C で暗闇の中で私たち以前紙38 - 基づき塩化p-toluenesulfenyl を格納して 3 ヵ月以内に使用してください。トリフラートの銀はぬれた、乾燥した真空中で O糖鎖の使用前にはずです。
このメソッドは、種々 のヌクレオシドと糖供与体 (表 1 2、および3) に適用でした。大規模な合成 β-28の主、α-32と18 (表 3エントリ 3) 必要な糖ヌクレオシドの分離が容易ではないの組み合わせなどいくつかの例を除いて成功。1"、二糖類ヌクレオシドの 5'-glicosidic リンケージの建設にこのメソッドを適用するさらに、(1 の建設」、2'- と 1 '、3'-glicosidic のリンケージがまだ調査される)。
無防備なヌクレオシドを用いたO糖鎖は、保護されたヌクレオシドを使用して、従来よりも短いプロセスで二糖類ヌクレオシドを提供します。
繰返しホウ酸エステルの一時的な保護を活用した無防備なヌクレオシドのO糖鎖は、様々 な生理活性糖ヌクレオシドおよびその類縁体の準備に適用でした。5 fluorouridine、5-フルオロウラシルがあるウイルス対策、抗癌、抗菌活動24,59,が知られているので、新しい薬剤の候補者をする β-35とその類縁を期待する特に、70,,7172,73,74,75,76。ホウ酸エステルによってヒドロキシル グループの一時保護のアプリケーションはさまざまな糖ヌクレオシドと同様、自然と人工の化合物の合成に有用であることを考えています。

ヌクレオシドと糖鎖の複合体である二糖類ヌクレオシド リンク経由で O-グリコシド結合、貴重な天然糖誘導体1,2 クラスを構成します。、3,4,5,6,7。例えば、彼らは tRNA (転送リボ核酸) や poly(ADP-ribose) などの生体高分子に組み込まれている (ADP = アデノシン二リン酸)、同様に、いくつかの抗菌薬とその他の生理活性物質 (例えば、adenophostins、amicetins、ezomycin)5,6,8,9,10、11,12,13、 14,15,16,17,18,19。したがって、糖ヌクレオシド及びその誘導体は、鉛化合物の創薬研究をする予定です。二糖類のヌクレオシドの合成のための方法論は 3 つのカテゴリーに分類されます。酵素O糖鎖修飾20,21, 化学N- グリコシル化反応5,9,16,22,23、 24, と化学O糖鎖修飾7,9,14,16,18,19,24、 25,26,27,28,29,30,31,32,33、 34,35,36,37。特に、化学 o-グリコシレーション立体選択的合成と糖ヌクレオシドの大量合成のための効率的な方法になります。前の研究は 2'-デオキシリボヌクレオシド合成2と、thioglycosyl ドナー 1、 p- toluenesulfenyl 塩化とトリフラート、銀の組み合わせを使用してのO糖鎖を与えることを示している、二糖類ヌクレオシド3 (図 1A; を使用を希望Ar = アリール、PG = 保護グループ)38。
以下のこれらの結果、 p- toluenesulfenyl 塩化/シルバー トリフラート プロモーター システムを適用する ribonucleosides のO糖鎖を開発しました。部分的に保護された ribonucleosides のO糖鎖のいくつかの例が示された7,9,14,16,18,をされている19 ,24,32,33,34,35,36,37、保護されていない、または一時的に保護の使用O糖鎖の糖受容体として ribonucleosides は、無視できるほど報告されています。したがって、保護されていない、または一時的に保護 ribonucleosides O位置選択的グリコシル化反応の開発と ribonucleosides のグループの操作を保護することがなくより有益な合成法を提供しました。Ribonucleosides のO位置選択的グリコシル化反応を達成するために我々 に焦点を当ててホウ素化合物ので位置および立体選択的アシル化、アルキル化、シリル化、および炭水化物の糖鎖のいくつかの例ボロンの援助を受けて誘導体または borinic 酸がずっと報告39,40,41,42,43,44,45 、46,47,48,49,50。この記事では、ribonucleosides経由でホウ酸エステル中間の 5'-ヒドロキシル グループでO位置選択的グリコシル化反応を利用した二糖類ヌクレオシドの合成手順をデモンストレーションします。ここで紹介する戦略、ホウ酸エステル中間6リボヌクレオシド4ボロン酸5でO位置選択的グリコシル化反応を可能にするとのエステル化反応によって与えられることだろう、二糖類ヌクレオシド8 (図 1B)51を与える thioglycosyl ドナー 7と 5'-ヒドロキシル グループ。また、ホウ酸エステルの形成を観察するための核磁気共鳴 (NMR) 分光法によるリボヌクレオシドとボロン酸の相互作用を調べた。ホウ酸エステル、糖鎖修飾反応するエステル化反応では、ホウ酸エステル、糖ドナーの加水分解を防ぐために無水条件を必要があります。この記事では、研究者・生化学のみならず他の分野で成功した糖鎖反作用のため無水条件を取得する一般的な手順を示します。

<table border="0" cellpadding="0" cellspacing="0" style="width:847px;" width="847">
	<colgroup>
		<col />
		<col />
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	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Silver trifluoromethanesulfonate</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">34945-61</td>
			<td style="width:232px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:241px;">Phenylboronic acid (contains varying amounts of anhydride)</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">B0857</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">p-Methoxyphenylboronic acid</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">321-69201</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:241px;">4-(Trifluoromethyl)phenylboronic acid (contains varying amounts of anhydride)</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">T1788</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:241px;">2,4-Difluorophenylboronic acid (contains varying amounts of anhydride)</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">D3391</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:241px;">Cyclopentylboronic acid (contains varying amounts of Anhydride)</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">C2442</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:241px;">4-Nitrophenylboronic acid (contains varying amounts of anhydride)</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">N0812</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:241px;">4-Hexylphenylboronic acid (contains varying amounts of anhydride)</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">H1489</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Adenosine</td>
			<td style="width:255px;">Merck KGaA</td>
			<td style="width:119px;">862.</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Guanosine</td>
			<td style="width:255px;">Acros Organics</td>
			<td align="right" style="width:119px;">411130050</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Cytidine</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">C0522</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Uridine</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">U0020</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">5-Fluorouridine</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">F0636</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">5-Methyluridine</td>
			<td style="width:255px;">Sigma</td>
			<td style="width:119px;">M-9885</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:241px;">Methylamine (40% in Methanol,&#160;ca. 9.8mol/L)</td>
			<td style="width:255px;">Tokyo Chemical Industry</td>
			<td style="width:119px;">M1016</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">N,N-dimethyl-4-aminopyridine</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">044-19211</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Acetic anhydride</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">00226-15</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Pyridine, Dehydrated</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">161-18453</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Acetonitrile</td>
			<td style="width:255px;">Kanto Chemical</td>
			<td style="width:119px;">01031-96</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">1,4-Dioxane</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">13622-73</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Dichloromethane</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">130-02457</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Propionitrile</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">164-04756</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Molecular sieves 4A powder</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">04168-65</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Molecular sieves 3A powder</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">04176-55</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Celite 545RVS</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">08034-85</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Acetonitrile-D3 (D,99.8%)</td>
			<td style="width:255px;">Cambridge Isotope Laboratories</td>
			<td style="width:119px;">DLM-21-10</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Trifluoroacetic acid</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">34831-25</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:241px;">TLC Silica gel 60 F254</td>
			<td style="width:255px;">Merck KGaA</td>
			<td style="width:119px;">1.05715.0001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Chromatorex</td>
			<td style="width:255px;">Fuji Silysia Chemical</td>
			<td style="width:119px;">FL100D</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Sodium hydrogen carbonate</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">191-01305</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Hydrochloric acid</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">080-01061</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Sodium sulfate</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">31915-96</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Chloroform</td>
			<td style="width:255px;">Kanto Chemical</td>
			<td style="width:119px;">07278-81</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Sodium chloride</td>
			<td style="width:255px;">Wako Pure Chemical Industries</td>
			<td style="width:119px;">194-01677</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Methanol</td>
			<td style="width:255px;">Nacalai Tesque</td>
			<td style="width:119px;">21914-74</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">JEOL Always 300</td>
			<td style="width:255px;">JEOL</td>
			<td style="width:119px;"></td>
			<td>Measurement of NMR</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Lamda 400</td>
			<td style="width:255px;">JEOL</td>
			<td style="width:119px;"></td>
			<td>Measurement of NMR</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:241px;">PerkinElmer Spectrum 100 FT-IR Spectrometer</td>
			<td style="width:255px;">Perkin Elmer</td>
			<td style="width:119px;"></td>
			<td>Measurement of IR</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">JEOL JMS-700</td>
			<td style="width:255px;">JEOL</td>
			<td style="width:119px;"></td>
			<td>Measurement of MS</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">PerkinElmer CHN 2400 analyzer</td>
			<td style="width:255px;">Perkin Elmer</td>
			<td style="width:119px;"></td>
			<td>Measurement of elemental analysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">JASCO P-1030 digital polarimeter</td>
			<td style="width:255px;">JASCO</td>
			<td style="width:119px;"></td>
			<td>Measurement of optical rotation</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:241px;">JASCO PU-2089 Plus intelligent HPLC pump</td>
			<td style="width:255px;">JASCO</td>
			<td style="width:119px;"></td>
			<td>For HPLC</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:241px;">Jasco UV-2075 Plus Intelligent UV/Vis Detector</td>
			<td style="width:255px;">JASCO</td>
			<td style="width:119px;"></td>
			<td>For HPLC</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Rheodyne Model 7125 Injector</td>
			<td style="width:255px;">Sigma-Aldrich</td>
			<td align="right" style="width:119px;">58826</td>
			<td>For HPLC</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Chromatopac C-R8A</td>
			<td style="width:255px;">Shimadzu</td>
			<td style="width:119px;"></td>
			<td>For HPLC</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">Senshu Pak Pegasil ODS</td>
			<td style="width:255px;">Senshu Scientific</td>
			<td style="width:119px;"></td>
			<td>For HPLC</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">p-Toluenesulfenyl&#160;chloride</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 38</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:241px;">Phenyl 6-O-acetyl-2,3,4-tri-O-benzyl-1-thio-a-D-mannopyranoside (a-9)</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 52</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:241px;">4-Metylphenyl 2,3,4,6-tetra-O-benzoyl-1-thio-b-D-galactopyranoside (b-21)</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 53</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:241px;">4-Metylphenyl 2,3,4,6-tetra-O-benzoyl-1-thio-b-D-glucopyranoside (b-31)</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 57</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:241px;">4-Metylphenyl 2,3,4,6-tetra-O-benzoyl-1-thio-a-D-Mannopyranoside (a-32)</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 67</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">6-N-Benzoyladenosine (14)</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 54</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">2-N-Isobutyrylguanosine (16)</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 55</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:241px;">4-N-Benzoylcytidine (20)</td>
			<td style="width:255px;"></td>
			<td style="width:119px;"></td>
			<td>Prepared&#160; Ref. 56</td>
		</tr>
	</tbody>
</table>

regioselective o-glycosylation of nucleosides via the temporary 2',3'-diol protection by a boronic ester for the synthesis of disaccharide nucleosides

二糖類、核酸塩基の部分から成って、二糖類ヌクレオシドは、多種多様な生物活性を有する天然物の貴重なグループとして知られています。面倒な保護グループの操作とで精製糖供与体と受容体などの基板の準備が必要です化学O糖鎖は糖ヌクレオシドの合成よく有益な戦略が、各合成のステップ。一方、いくつかの研究グループが、ボロン報告し、borinic エステルが、保護または位置および立体選択的アシル化、アルキル化、シリル化、グリコシル化反応を達成するために糖誘導体のグループをアクティブにします。この記事では、ボロン酸を利用した保護されていない ribonucleosides のO位置選択的グリコシル化反応の手順を示します。2' のエステル化、ボロン酸と ribonucleosides の 3'-ジオールは、 ptoluenesulfenyl の存在下で糖のドナーとジオール、次 o-グリコシレーションの一時的な保護塩化と銀トリフラート、許可二糖類ヌクレオシドを余裕に 5'-ヒドロキシル グループの位置選択的反応。このメソッドは、グアノシン、アデノシン、シチジン、ウリジン、5-metyluridine、5 fluorouridine などの様々 なヌクレオシドに適用でした。この記事と付属のビデオ無防備なヌクレオシドのO糖鎖についての役に立つ (ビジュアル) と糖ヌクレオシドのみならず、さまざまな生物学的関連性の合成、類縁を表します誘導体。

Watch this Scientific Journal Video about Regioselective O-Glycosylation of Nucleosides via the Temporary 2',3'-Diol Protection by a Boronic Ester for the Synthesis of Disaccharide Nucleosides at JoVE

Regioselective O-Glycosylation of Nucleosides via the Temporary 2',3'-Diol Protection by a Boronic Ester for the Synthesis of Disaccharide Nucleosides

今回二糖類ヌクレオシドの合成のためのプロトコルを介してribonucleosides のO位置選択的グリコシル化反応での一時的な保護、2'、3'-ジオール部分繰返しホウ酸エステルを利用しました。このメソッドは、いくつかの無防備なヌクレオシド アデノシン, グアノシン、シチジン、ウリジン、5-メチルウリジン, 対応する糖ヌクレオシドを与える 5 fluorouridine などに適用されます。

ヌクレオシドを介して一時 2'、3'-ジオール保護ホウ酸エステル糖ヌクレオシドの合成のためのOの位置選択的グリコシル化反応

Disaccharide nucleosides, which consist of disaccharide and nucleobase moieties, have been known as a valuable group of natural products having ...

regioselective-o-glycosylation-nucleosides-via-temporary-2-3-diol

Nanyang Technological University

Research

JoVE Journal

Chemistry

Regioselective O-Glycosylation of Nucleosides via the Temporary 2',3'-Diol Protection by a Boronic Ester for the Synthesis of Disaccharide Nucleosides

8.6K ビュー.  Tokyo University of Science. 今回二糖類ヌクレオシドの合成のためのプロトコルを介してribonucleosides のO位置選択的グリコシル化反応での一時的な保護、2'、3'-ジオール部分繰返しホウ酸エステルを利用しました。このメソッドは、いくつかの無防備なヌクレオシド アデノシン, グアノシン、シチジン、ウリジン、5-メチルウリジン, 対応する糖ヌクレオシドを与える 5 flu...

ビデオ: Regioselective O-Glycosylation of Nucleosides via the Temporary 2',3'-Diol Protection by a Boronic Ester for the Synthesis of Disaccharide Nucleosides

Anticancer Metal Complexes: Synthesis and Cytotoxicity Evaluation by the MTT Assay

Titanium (IV) and vanadium (V) complexes are highly potent anticancer agents. A challenge in their synthesis refers to their hydrolytic instability; therefore their preparation should be conducted under an inert atmosphere. Evaluation of the anticancer activity of these complexes can be achieved by the MTT assay.
The MTT assay is a colorimetric viability assay based on enzymatic reduction of the MTT molecule to formazan when it is exposed to viable cells. The outcome of the reduction is a color change of the MTT molecule. Absorbance measurements relative to a control determine the percentage of remaining viable cancer cells following their treatment with varying concentrations of a tested compound, which is translated to the compound anticancer activity and its IC50 values. The MTT assay is widely common in cytotoxicity studies due to its accuracy, rapidity, and relative simplicity.
Herein we present a detailed protocol for the synthesis of air sensitive metal based drugs and cell viability measurements, including preparation of the cell plates, incubation of the compounds with the cells, viability measurements using the MTT assay, and determination of IC50 values.

A method for synthesis of air-sensitive titanium and vanadium anticancer agents is described, along with the evaluation of their cytotoxic activity towards human cancer cell line by the MTT Assay.

MTTアッセイにより合成と細胞毒性の評価：抗がん金属錯体

Titanium (IV) and vanadium (V) complexes are highly potent anticancer agents. A challenge in their synthesis refers to their hydrolytic instability; ...

化学

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control self-assembly and mimicking this process in vitro will bring about major advances in the areas of materials science and nanotechnology. Among the available biological building blocks, peptides have several advantages as they present substantial diversity, their synthesis in large scale is straightforward, and they can easily be modified with biological and chemical entities1,2. Several classes of designed peptides such as cyclic peptides, amphiphile peptides and peptide-conjugates self-assemble into ordered structures in solution. Homoaromatic dipeptides, are a class of short self-assembled peptides that contain all the molecular information needed to form ordered structures such as nanotubes, spheres and fibrils3-8. A large variety of these peptides is commercially available.
This paper presents a procedure that leads to the formation of ordered structures by the self-assembly of homoaromatic peptides. The protocol requires only commercial reagents and basic laboratory equipment. In addition, the paper describes some of the methods available for the characterization of peptide-based assemblies. These methods include electron and atomic force microscopy and Fourier-Transform Infrared Spectroscopy (FT-IR). Moreover, the manuscript demonstrates the blending of peptides (coassembly) and the formation of a &#34;beads on a string&#34;-like structure by this process.9 The protocols presented here can be adapted to other classes of peptides or biological building blocks and can potentially lead to the discovery of new peptide-based structures and to better control of their assembly.

This paper describes the formation of highly ordered peptide-based structures by the spontaneous process of self-assembly. The method utilizes commercially available peptides and common lab equipment. This technique can be applied to a large variety of peptides and may lead to the discovery of new peptide-based assemblies.

短いペプチドの自己組織化によって順序付け生体分子構造の形成

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control ...

Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid phase by using combinatorial chemistry. One of the most well studied classes of peptidomimetics is peptoids. Peptoids are easy to synthesize and have been shown to be proteolysis-resistant and cell-permeable. Over the past decade, many useful protein ligands have been identified through screening of peptoid libraries. However, most of the ligands identified from peptoid libraries do not display high affinity, with rare exceptions. This may be due, in part, to the lack of chiral centers and conformational constraints in peptoid molecules. Recently, we described a new synthetic route to access peptide tertiary amides (PTAs). PTAs are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. With side chains on both &#945;-carbon and main chain nitrogen atoms, the conformation of these molecules are greatly constrained by sterical hindrance and allylic 1,3 strain. (Figure 1) Our study suggests that these PTA molecules are highly structured in solution and can be used to identify protein ligands. We believe that these molecules can be a future source of high-affinity protein ligands. Here we describe the synthetic method combining the power of both split-and-pool and sub-monomer strategies to synthesize a sample one-bead one-compound (OBOC) library of PTAs.

Peptide tertiary amides (PTAs) are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. Here we describe a synthetic method which combines&#160;both split-and-pool and sub-monomer strategies to synthesize a one-bead one-compound library of PTAs.

ペプチド第三級アミドライブラリのスプリット·アンド·プールの合成とキャラクタリゼーション

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid ...

Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. Diiodomethyllithium is prepared by the deprotonation of diiodomethane with LiHMDS, in a THF/diethyl ether mixture, at -78 &#176;C in the dark. These conditions are essential for the stability of the LiCHI2 reagent generated. The subsequent dropwise addition of N-Ts aldimines to the preformed diiodomethyllithium solution affords an amino-diiodide intermediate, which is not isolated. Rapid warming of the reaction mixture to 0 &#176;C promotes cyclization to afford iodoaziridines with exclusive cis-diastereoselectivity. The addition and cyclization stages of the reaction are mediated in one reaction flask by careful temperature control.
Due to the sensitivity of the iodoaziridines to purification, assessment of suitable methods of purification is required. A protocol to assess the stability of sensitive compounds to stationary phases for column chromatography is described. This method is suitable to apply to new iodoaziridines, or other potentially sensitive novel compounds. Consequently this method may find application in range of synthetic projects. The procedure involves firstly the assessment of the reaction yield, prior to purification, by 1H NMR spectroscopy with comparison to an internal standard. Portions of impure product mixture are then exposed to slurries of various stationary phases appropriate for chromatography, in a solvent system suitable as the eluent in flash chromatography. After stirring for 30 min to mimic chromatography, followed by filtering, the samples are analyzed by 1H NMR spectroscopy. Calculated yields for each stationary phase are then compared to that initially obtained from the crude reaction mixture. The results obtained provide a quantitative assessment of the stability of the compound to the different stationary phases; hence the optimal can be selected. The choice of basic alumina, modified to activity IV, as a suitable stationary phase has allowed isolation of certain iodoaziridines in excellent yield and purity.

A protocol for the diastereoselective one-pot preparation of cis-N-Ts-iodoaziridines is described. The generation of diiodomethyllithium, addition to N-Ts aldimines and cyclization of the amino gem-diiodide intermediate to iodoaziridines is demonstrated. Also included is a protocol to rapidly and quantitatively assess the most appropriate stationary phase for purification by chromatography.

クロマトグラフィーのための最適な固定相の定量的な選択を伴う合成とIodoaziridinesの精製

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. ...

HKUST-1 as a Heterogeneous Catalyst for the Synthesis of Vanillin

Vanillin (4-hydoxy-3-methoxybenzaldehyde) is the main component of the extract of vanilla bean. The natural vanilla scent is a mixture of approximately 200 different odorant compounds in addition to vanillin. The natural extraction of vanillin (from the orchid Vanilla planifolia, Vanilla tahitiensis and Vanilla pompon) represents only 1% of the worldwide production and since this process is expensive and very long, the rest of the production of vanillin is synthesized. Many biotechnological approaches can be used for the synthesis of vanillin from lignin, phenolic stilbenes, isoeugenol, eugenol, guaicol, etc., with the disadvantage of harming the environment since these processes use strong oxidizing agents and toxic solvents. Thus, eco-friendly alternatives on the production of vanillin are very desirable and thus, under current investigation. Porous coordination polymers (PCPs) are a new class of highly crystalline materials that recently have been used for catalysis. HKUST-1 (Cu3(BTC)2(H2O)3, BTC = 1,3,5-benzene-tricarboxylate) is a very well known PCP which has been extensively studied as a heterogeneous catalyst. Here, we report a synthetic strategy for the production of vanillin by the oxidation of trans-ferulic acid using HKUST-1 as a catalyst.

The conversion of trans-ferulic acid to vanillin was achieved by heterogeneous catalysis. HKUST-1 was employed in this synthesis and the essential step in the catalytic process was the generation of unsaturated metal sites. Thus, when the catalyst was activated under vacuum, full vanillin conversion (yield of 95%) was obtained.

HKUST-1バニリンの合成のための不均一触媒として、

Vanillin (4-hydoxy-3-methoxybenzaldehyde) is the main component of the extract of vanilla bean. The natural vanilla scent is a mixture of approximately ...

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

The chemical linking or bioconjugation of proteins to fluorescent dyes, drugs, polymers and other proteins has a broad range of applications, such as the development of antibody drug conjugates (ADCs) and nanomedicine, fluorescent microscopy and systems chemistry. For many of these applications, specificity of the bioconjugation method used is of prime concern. The Michael addition of maleimides with cysteine(s) on the target proteins is highly selective and proceeds rapidly under mild conditions, making it one of the most popular methods for protein bioconjugation.
We demonstrate here the modification of the only surface-accessible cysteine residue on yeast cytochrome c with a ruthenium(II) bisterpyridine maleimide. The protein bioconjugation is verified by gel electrophoresis and purified by aqueous-based fast protein liquid chromatography in 27% yield of isolated protein material. Structural characterization with MALDI-TOF MS and UV-Vis is then used to verify that the bioconjugation is successful. The protocol shown here is easily applicable to other cysteine - maleimide coupling of proteins to other proteins, dyes, drugs or polymers.

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

This protocol details the important steps required for the bioconjugation of a cysteine containing protein to a maleimide, including reagent purification, reaction conditions, bioconjugate purification and bioconjugate characterization.

タンパク質のバイオコンジュゲートの合成<em&gt;経由で</em&gt;システイン - マレイミドケミストリー

The chemical linking or bioconjugation of proteins to fluorescent dyes, drugs, polymers and other proteins has a broad range of applications, such as the ...

Facile Synthesis of Worm-like Micelles by Visible Light Mediated Dispersion Polymerization Using Photoredox Catalyst

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins with the synthesis of a hydrophilic poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) homopolymer using reversible addition-fragmentation chain-transfer (RAFT) polymerization. Under mild visible light irradiation (&#955; = 460 nm, 0.7 mW/cm2), this macro-chain transfer agent (macro-CTA) in the presence of a ruthenium based photoredox catalyst, Ru(bpy)3Cl2 can be chain extended with a second monomer to form a well-defined block copolymer in a process known as Photoinduced Electron Transfer RAFT (PET-RAFT). When PET-RAFT is used to chain extend POEGMA with benzyl methacrylate (BzMA) in ethanol (EtOH), polymeric nanoparticles with different morphologies are formed in situ according to a polymerization-induced self-assembly (PISA) mechanism. Self-assembly into nanoparticles presenting POEGMA chains at the corona and poly(benzyl methacrylate) (PBzMA) chains in the core occurs in situ due to the growing insolubility of the PBzMA block in ethanol. Interestingly, the formation of highly pure worm-like micelles can be readily monitored by observing the onset of a highly viscous gel in situ due to nanoparticle entanglements occurring during the polymerization. This process thereby allows for a more reproducible synthesis of worm-like micelles simply by monitoring the solution viscosity during the course of the polymerization. In addition, the light stimulus can be intermittently applied in an ON/OFF manner demonstrating temporal control over the nanoparticle morphology.

This article describes a process for producing polymeric self-assembled nanoparticles using visible light mediated dispersion polymerization. Using low energy visible light to control the polymerization allows for the reproducible formation of self-assembled worm-like micelles at high solids content.

Photoredox触媒を用いた可視光媒介分散重合によるワームのようなミセルの簡便な合成

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins ...

Hydroquinone Based Synthesis of Gold Nanorods

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the synthetic methods for the preparation of gold nanorods are still not fully optimized. In this paper we describe a new, highly efficient, two-step protocol based on the use of hydroquinone as a mild reducing agent. Our approach allows the preparation of nanorods with a good control of size and aspect ratio (AR) simply by varying the amount of hexadecyl trimethylammonium bromide (CTAB) and silver ions (Ag+) present in the "growth solution". By using this method, it is possible to markedly reduce the amount of CTAB, an expensive and cytotoxic reagent, necessary to obtain the elongated shape. Gold nanorods with an aspect ratio of about 3 can be obtained in the presence of just 50 mM of CTAB (versus 100 mM used in the standard protocol based on the use of ascorbic acid), while shorter gold nanorods are obtained using a concentration as low as 10 mM.

This paper describes a protocol for the synthesis of gold nanorods, based on the use of hydroquinone as reducing agent, plus the different mechanisms for controlling their size and aspect ratio.

金ナノロッドのヒドロキノンベースの合成

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the ...

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular methodology for applications in various fields and for different research purposes. The procedure described herein focuses on the synthesis, purification, and characterization of dodecamers of RNA 5&#39;-[CUA CGG AAU CAU]-3&#39; containing zero, one, or two modifications located at the C2&#39;-O-position. The probes are based on 2-thiophenylmethyl groups, incorporated into RNA nucleotides via standard organic synthesis and introduced into the corresponding oligonucleotides via their respective phosphoramidites. This report makes use of phosphoramidite chemistry via the four canonical nucleobases (Uridine (U), Cytosine (C), Guanosine (G), Adenosine (A)), as well as 2-thiophenylmethyl functionalized nucleotides modified at the 2&#39;-O-position; however, the methodology is amenable for a large variety of modifications that have been developed over the years. The oligonucleotides were synthesized on a controlled-pore glass (CPG) support followed by cleavage from the resin and deprotection under standard conditions, i.e., a mixture of ammonia and methylamine (AMA) followed by hydrogen fluoride/triethylamine/N-methylpyrrolidinone. The corresponding oligonucleotides were purified via polyacrylamide electrophoresis (20% denaturing) followed by elution, desalting, and isolation via reversed-phase chromatography (Sep-pak, C18-column). Quantification and structural parameters were assessed via ultraviolet-visible (UV-vis) and circular dichroism (CD) photometric analysis, respectively. This report aims to serve as a resource and guide for beginner and expert researchers interested in embarking in this field. It is expected to serve as a work-in-progress as new technologies and methodologies are developed. The description of the methodologies and techniques within this document correspond to a DNA/RNA synthesizer (refurbished and purchased in 2013) that uses phosphoramidite chemistry.

Protocol for the Solid-phase Synthesis of Oligomers of RNA Containing a 2'-O-thiophenylmethyl Modification and Characterization via Circular Dichroism

This article provides a detailed procedure on the solid-phase synthesis, purification, and characterization of dodecamers of RNA modified at the C2&#39;-O-position. UV-vis and circular dichroism photometric analyses are used to quantify and characterize structural aspects, i.e., single-strands or double-strands.

2 &#39;末端を含むRNAのオリゴマーの固相合成のためのプロトコール<em&gt; O</em&gt;チオフェンメチル修飾と環状二色性によるキャラクタリゼーション

Solid-phase synthesis has been used to obtain canonical and modified polymers of nucleic acids, specifically of DNA or RNA, which has made it a popular ...

Synthesis of Substrate-Bound Au Nanowires Via an Active Surface Growth Mechanism

Advancing synthetic capabilities is important for the development of nanoscience and nanotechnology. The synthesis of nanowires has always been a challenge, as it requires asymmetric growth of symmetric crystals. Here, we report a distinctive synthesis of substrate-bound Au nanowires. This template-free synthesis employs thiolated ligands and substrate adsorption to achieve the continuous asymmetric deposition of Au in solution at ambient conditions. The thiolated ligand prevented the Au deposition on the exposed surface of the seeds, so the Au deposition only occurs at the interface between the Au seeds and the substrate. The side of the newly deposited Au nanowires is immediately covered with the thiolated ligand, while the bottom facing the substrate remains ligand-free and active for the next round of Au deposition. We further demonstrate that this Au nanowire growth can be induced on various substrates, and different thiolated ligands can be used to regulate the surface chemistry of the nanowires. The diameter of the nanowires can also be controlled with mixed ligands, in which another &#34;bad&#34; ligand could turn on the lateral growth. With the understanding of the mechanism, Au nanowire-based nanostructures can be designed and synthesized.

We report a solution-based method to synthesize substrate-bound Au nanowires. By tuning the molecular ligands used during the synthesis, the Au nanowires can be grown from various substrates with different surface properties. Au nanowire-based nanostructures can also be synthesized by adjusting the reaction parameters.