Category: 367-93-1

Aspergillus nidulans AmyG functions as an intracellular α-amylase to promote α-glucan synthesis was written by Kazim, Alia Rizvi Syeda;Jiang, Yuting;Li, Shengnan;He, Xiaoxiao. And the article was included in Microbiology Spectrum in 2021.Reference of 367-93-1 The following contents are mentioned in the article:

α-Glucan is a major cell wall component and a virulence and adhesion factor for fungal cells. However, the biosynthetic pathway of α-glucan was still unclear. α-Glucan was shown to be composed mainly of 1,3-glycosidically linked glucose, with trace amounts of 1,4-glycosidically linked glucose. Besides the α-glucan synthetases, amylase-like proteins were also important for α-glucan synthesis. In our previous work, we showed that Aspergillus nidulans AmyG was an intracellular protein and was crucial for the proper formation of α-glucan. In the present study, we expressed and purified AmyG in an Escherichia coli system. Enzymic characterization found that AmyG mainly functioned as an α-amylase that degraded starch into maltose. AmyG also showed weak glucano-transferase activity. Most intriguingly, supplementation with maltose in shaken liquid medium could restore the α-glucan content and the phenotypic defect of a ΔamyG strain. These data suggested that AmyG functions mainly as an intracellular α-amylase to provide maltose during α-glucan synthesis in A. nidulans. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Reference of 367-93-1).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. A strong base can deprotonate an alcohol to yield an alkoxide ion (R―O−). For example, sodamide (NaNH2), a very strong base, abstracts the hydrogen atom of an alcohol. Alcohols may be oxidized to give ketones, aldehydes, and carboxylic acids. These functional groups are useful for further reactions. Oxidation of organic compounds generally increases the number of bonds from carbon to oxygen (or another electronegative element, such as a halogen), and it may decrease the number of bonds to hydrogen.Reference of 367-93-1

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Bioengineered bacteria-derived outer membrane vesicles as a versatile antigen display platform for tumor vaccination via Plug-and-Display technology was written by Cheng, Keman;Zhao, Ruifang;Li, Yao;Qi, Yingqiu;Wang, Yazhou;Zhang, Yinlong;Qin, Hao;Qin, Yuting;Chen, Long;Li, Chen;Liang, Jie;Li, Yujing;Xu, Jiaqi;Han, Xuexiang;Anderson, Gregory J.;Shi, Jian;Ren, Lei;Zhao, Xiao;Nie, Guangjun. And the article was included in Nature Communications in 2021.Safety of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol The following contents are mentioned in the article:

An effective tumor vaccine vector that can rapidly display neoantigens is urgently needed. Outer membrane vesicles (OMVs) can strongly activate the innate immune system and are qualified as immunoadjuvants. Here, we describe a versatile OMV-based vaccine platform to elicit a specific anti-tumor immune response via specifically presenting antigens onto OMV surface. We first display tumor antigens on the OMVs surface by fusing with ClyA protein, and then simplify the antigen display process by employing a Plug-and-Display system comprising the tag/catcher protein pairs. OMVs decorated with different protein catchers can simultaneously display multiple, distinct tumor antigens to elicit a synergistic antitumor immune response. In addition, the bioengineered OMVs loaded with different tumor antigens can abrogate lung melanoma metastasis and inhibit s.c. colorectal cancer growth. The ability of the bioengineered OMV-based platform to rapidly and simultaneously display antigens may facilitate the development of these agents for personalized tumor vaccines. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Safety of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. A strong base can deprotonate an alcohol to yield an alkoxide ion (R―O−). For example, sodamide (NaNH2), a very strong base, abstracts the hydrogen atom of an alcohol. Tertiary alcohols cannot be oxidized at all without breaking carbon-carbon bonds, whereas primary alcohols can be oxidized to aldehydes or further oxidized to carboxylic acids.Safety of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Enhanced Production Process of Recombinant Mature Serratiopeptidase in Escherichia coli Using Fed-Batch Culture by Self-Proteolytic Activity of Fusion Protein was written by Doshi, Pooja;Dantroliya, Sadik;Modi, Akhilesh;Shukla, Arpit;Patel, Dhaval;Joshi, Chaitanya;Joshi, Madhvi. And the article was included in Fermentation in 2022.Electric Literature of C9H18O5S The following contents are mentioned in the article:

Microbial enzymes are increasingly finding applications as therapeutics due to their targeted activity and minimal side effects. Serratiopeptidase, also known as a miracle enzyme, has already proved its potential as an anti-inflammatory, mucolytic, fibrinolytic, analgesic in many studies. A cost effective, bioreactor level production process has been described here comprising of the fed-batch fermentation to produce recombinant serratiopeptidase protein expressed as a fusion construct. High yield of cell mass as well as protein was obtained by the optimization of bioreactor parameters. The downstream solubilization and purification processes were also optimized to achieve maximum yield of pure, active serratiopeptidase protein. A final yield of 2.5 ± 0.764 g L^-1 of protein was obtained, having 8382 ± 291 U mg^-1 of specific caseinolytic activity. Addnl., a novel, unexpected self-proteolytic activity of the enzyme that cleaves the N-terminal 6x His-SUMO fusion tag along with the enzyme propeptide, thus yielding a mature serratiopeptidase, was also found. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Electric Literature of C9H18O5S).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. Because alcohols are easily synthesized and easily transformed into other compounds, they serve as important intermediates in organic synthesis. A multistep synthesis may use Grignard-like reactions to form an alcohol with the desired carbon structure, followed by reactions to convert the hydroxyl group of the alcohol to the desired functionality.Electric Literature of C9H18O5S

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Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Metabolic engineering of Escherichia coli with electron channelling for the production of natural products was written by Park, Seon Young;Eun, Hyunmin;Lee, Mun Hee;Lee, Sang Yup. And the article was included in Nature Catalysis in 2022.HPLC of Formula: 367-93-1 The following contents are mentioned in the article:

The biosynthesis of natural products often requires eukaryotic cytochrome P450s (P450s) in combination with P 450 reductase, in phys. proximity, to perform electron-transfer reactions. Unfortunately, functional expression of eukaryotic P450s in bacteria remains generally difficult. Here we report an electron channeling strategy based on the application of Photorhabdus luminescens CipB scaffold protein, which allows efficient electron transfer between P450s and reductases by bringing these enzymes in close proximity. The general applicability of this electron channeling strategy is proved by developing recombinant Escherichia coli strains producing lutein, (+)-nootkatone, apigenin and L-3,4-dihydroxyphenylalanine (L-DOPA), each of which requires P450s in its biosynthetic pathway. The production titers are then further enhanced by increasing the haem pathway flux or by optimization of the culture conditions. Remarkably, the final lutein strain produced 218.0 mg l-1 of lutein with a productivity of 5.01 mg l-1 h-1 in fed-batch fermentation under optimized culture conditions. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1HPLC of Formula: 367-93-1).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. Because alcohols are easily synthesized and easily transformed into other compounds, they serve as important intermediates in organic synthesis. Under carefully controlled conditions, simple alcohols can undergo intermolecular dehydration to give ethers. This reaction is effective only with methanol, ethanol, and other simple primary alcohols.HPLC of Formula: 367-93-1

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

The Longitudinal Dividing Bacterium Candidatus Thiosymbion Oneisti Has a Natural Temperature-Sensitive FtsZ Protein with Low GTPase Activity was written by Wang, Jinglan;Bulgheresi, Silvia;den Blaauwen, Tanneke. And the article was included in International Journal of Molecular Sciences in 2022.Electric Literature of C9H18O5S The following contents are mentioned in the article:

FtsZ, the bacterial tubulin-homolog, plays a central role in cell division and polymerizes into a ring-like structure at midcell to coordinate other cell division proteins. The rod-shaped gamma-proteobacterium Candidatus Thiosymbion oneisti has a medial discontinuous ellipsoidal “Z-ring.” Ca. T. oneisti FtsZ shows temperature-sensitive characteristics when it is expressed in Escherichia coli, where it localizes at midcell. The overexpression of Ca. T. oneisti FtsZ interferes with cell division and results in filamentous cells. In addition, it forms ring- and barrel-like structures independently of E. coli FtsZ, which suggests that the difference in shape and size of the Ca. T. oneisti FtsZ ring is likely the result of its interaction with Z-ring organizing proteins. Similar to some temperature-sensitive alleles of E. coli FtsZ, Ca. T. oneisti FtsZ has a weak GTPase and does not polymerize in vitro. The temperature sensitivity of Ca. Thiosymbion oneisti FtsZ is likely an adaptation to the preferred temperature of less than 30°C of its host, the nematode Laxus oneistus. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Electric Literature of C9H18O5S).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. A strong base can deprotonate an alcohol to yield an alkoxide ion (R―O−). For example, sodamide (NaNH2), a very strong base, abstracts the hydrogen atom of an alcohol. The most common reactions of alcohols can be classified as oxidation, dehydration, substitution, esterification, and reactions of alkoxides.Electric Literature of C9H18O5S

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Structural and Functional Analysis of Bacterial Sulfonosphingolipids and Rosette-Inducing Factor 2 (RIF-2) by Mass Spectrometry-Guided Isolation and Total Synthesis was written by Leichnitz, Daniel;Peng, Chia-Chi;Raguz, Luka;Rutaganira, Florentine U. N.;Jautzus, Theresa;Regestein, Lars;King, Nicole;Beemelmanns, Christine. And the article was included in Chemistry – A European Journal in 2022.Quality Control of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol The following contents are mentioned in the article:

We have analyzed the abundance of bacterial sulfonosphingolipids, including rosette-inducing factors (RIFs), in seven bacterial prey strains by using high-resolution tandem mass spectrometry (HRMS2) and mol. networking (MN) within the Global Natural Product Social Mol. Networking (GNPS) web platform. Six sulfonosphingolipids resembling RIFs were isolated and their structures were elucidated based on comparative MS and NMR studies. Here, we also report the first total synthesis of two RIF-2 diastereomers and one congener in 15 and eight synthetic steps, resp. For the total synthesis of RIF-2 congeners, we employed a decarboxylative cross-coupling reaction to synthesize the necessary branched α-hydroxy fatty acids, and the Garner-aldehyde approach to generate the capnine base carrying three stereogenic centers. Bioactivity studies in the choanoflagellate Salpingoeca rosetta revealed that the rosette inducing activity of RIFs is inhibited dose dependently by the co-occurring sulfonosphingolipid sulfobacins D and F and that activity of RIFs is specific for isolates obtained from Algoriphagus. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Quality Control of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. Similar to water, an alcohol can be pictured as having an sp3 hybridized tetrahedral oxygen atom with nonbonding pairs of electrons occupying two of the four sp3 hybrid orbitals. Alcohols may be oxidized to give ketones, aldehydes, and carboxylic acids. These functional groups are useful for further reactions. Oxidation of organic compounds generally increases the number of bonds from carbon to oxygen (or another electronegative element, such as a halogen), and it may decrease the number of bonds to hydrogen.Quality Control of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Engineering metabolic pathways for cofactor self-sufficiency and serotonin production in Escherichia coli was written by Shen, Peijie;Gu, Suyi;Jin, Dou;Su, Yu;Wu, Hongxuan;Li, Qingchen;Yang, Jinhua;He, Wenjin;Huang, Jianzhong;Qi, Feng. And the article was included in ACS Synthetic Biology in 2022.Category: alcohols-buliding-blocks The following contents are mentioned in the article:

Serotonin is a neurotransmitter that plays an essential regulatory role in numerous cognitive and behavioral functions. Recent advances in synthetic biol. have enabled engineering of non-natural biosynthetic pathways for serotonin production in E. coli. Here, an optimized heterologous serotonin biosynthetic pathway was engineered in E. coli and coupled with the biosynthetic and regeneration modules of the endogenous vital cofactor tetrahydrobiopterin (BH4) for efficient serotonin production using whole-cell catalysis. Further metabolic engineering efforts were performed to ensure an adequate endogenous BH4 supply, including enhancements of GTP biosynthesis and intracellular reducing power availability. Using the optimized fed-batch fermentation, an overall maximum serotonin yield of 40.3% (mol/mol) and a peak titer of 1.68 g/L (production rate of 0.016 g/L/h) were achieved. The strategies employed in this study show the promise of using E. coli for pterin self-sufficiency and high-level serotonin production, and the engineered strains hold the potential for use in industrial applications. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Category: alcohols-buliding-blocks).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. A strong base can deprotonate an alcohol to yield an alkoxide ion (R―O−). For example, sodamide (NaNH2), a very strong base, abstracts the hydrogen atom of an alcohol. Grignard and organolithium reagents are powerful tools for organic synthesis, and the most common products of their reactions are alcohols.Category: alcohols-buliding-blocks

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Glycosyltransferase from Bacteroides gallinaceum Is a Novel α-1,3-Fucosyltransferase that Can Be Used for 3-Fucosyllactose Production In Vivo by Metabolically Engineered Escherichia coli was written by Chen, Geng;Wu, Hao;Zhu, Yingying;Wan, Li;Zhang, Wenli;Mu, Wanmeng. And the article was included in Journal of Agricultural and Food Chemistry in 2022.Application In Synthesis of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol The following contents are mentioned in the article:

As one of the attractive fucosylated human milk oligosaccharides, the biol. production of 3-fucosyllactose (3-FL) has received great attention, as it exhibits many excellent physiol. functions for infants. In this work, a novel 3-FL-producing α-1,3-fucosyltransferase (α1,3-FucT) named FutM2 from Bacteroides gallinaceum was first selected from nine potential candidates in the NCBI database. Then, a highly 3-FL-producing engineered Escherichia coli strain was constructed by modular pathway enhancement including the GDL-L-fucose precursor supply by overexpressing manC, manB, gmd, and wcaG (CBGW), and the 3-FL synthesis pathway by introducing B. gallinaceum FutM2. Finally, a titer of 20.3 g L^-1 and productivity of 0.40 g L^-1 h^-1 of 3-FL were achieved in the 3-L bioreactor by engineered E. coli (ΔlacZΔwcaJ) harboring pCDF-CBGW and pET-futM2. Our study provided a novel α1,3-FucT from B. gallinaceum that could be used for 3-FL production, presenting an efficient microbial cell factory platform to de novo synthesize 3-FL from glycerol. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Application In Synthesis of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. Alcohols are weak acids. The most acidic simple alcohols (methanol and ethanol) are about as acidic as water, and most other alcohols are somewhat less acidic. Under carefully controlled conditions, simple alcohols can undergo intermolecular dehydration to give ethers. This reaction is effective only with methanol, ethanol, and other simple primary alcohols.Application In Synthesis of (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Versatility in acyltransferase activity completes chicoric acid biosynthesis in purple coneflower was written by Fu, Rao;Zhang, Pingyu;Jin, Ge;Wang, Lianglei;Qi, Shiqian;Cao, Yang;Martin, Cathie;Zhang, Yang. And the article was included in Nature Communications in 2021.Recommanded Product: (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol The following contents are mentioned in the article:

Purple coneflower (Echinacea purpurea (L.) Moench) is a popular native North American herbal plant. Its major bioactive compound, chicoric acid, is reported to have various potential physiol. functions, but little is known about its biosynthesis. Here, taking an activity-guided approach, we identify two cytosolic BAHD acyltransferases that form two intermediates, caftaric acid and chlorogenic acid. Surprisingly, a unique serine carboxypeptidase-like acyltransferase uses chlorogenic acid as its acyl donor and caftaric acid as its acyl acceptor to produce chicoric acid in vacuoles, which has evolved its acyl donor specificity from the better-known 1-O-β-D-glucose esters typical for this specific type of acyltransferase to chlorogenic acid. This unusual pathway seems unique to Echinacea species suggesting convergent evolution of chicoric acid biosynthesis. Using these identified acyltransferases, we have reconstituted chicoric acid biosynthesis in tobacco. Our results emphasize the flexibility of acyltransferases and their roles in the evolution of specialized metabolism in plants. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Recommanded Product: (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. Under appropriate conditions, inorganic acids also react with alcohols to form esters. To form these esters, a wide variety of specialized reagents and conditions can be used. Alcohols may be oxidized to give ketones, aldehydes, and carboxylic acids. These functional groups are useful for further reactions. Oxidation of organic compounds generally increases the number of bonds from carbon to oxygen (or another electronegative element, such as a halogen), and it may decrease the number of bonds to hydrogen.Recommanded Product: (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts

Genetic and bioprocess engineering for the selective and high-level production of geranyl acetate in Escherichia coli was written by Wang, Xun;Zhang, Xinyi;Zhang, Jia;Xiao, Longjie;Zhou, Yujunjie;Zhang, Yu;Wang, Fei;Li, Xun. And the article was included in ACS Sustainable Chemistry & Engineering in 2022.Related Products of 367-93-1 The following contents are mentioned in the article:

Geranyl acetate is, as one of the monoterpenoids, a natural constituent of more than 60 essential oils. Production of such an ester fragrance compound by plant extracts is limited by low yield and high processing costs but plausible by microbial synthesis. We report a microbial cell factory that realizes selective and high-level geranyl acetate production in Escherichia coli. For this purpose, co-expression of geraniol synthase and alc. acetyltransferase was initially used to increase production yield, but a considerable quantity of precursor geraniol was also produced. Further, introducing an extra AAT gene copy and controlling the substrate glycerol supply enabled a drastically higher selective geranyl acetate production Eventually, the highest reported titer of 52.78 mM (equivalent to 10.36 g/L) geranyl acetate, accounting for 98.5% of total products, was achieved under a controlled fermentation system. Such selective and high-level geranyl acetate production by combining genetic and bioprocess engineering is also a promising strategy for other monoterpene esters in E. coli. This study involved multiple reactions and reactants, such as (2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1Related Products of 367-93-1).

(2R,3R,4S,5R,6S)-2-(Hydroxymethyl)-6-(isopropylthio)tetrahydro-2H-pyran-3,4,5-triol (cas: 367-93-1) belongs to alcohols. Similar to water, an alcohol can be pictured as having an sp3 hybridized tetrahedral oxygen atom with nonbonding pairs of electrons occupying two of the four sp3 hybrid orbitals. Alcohols may be oxidized to give ketones, aldehydes, and carboxylic acids. These functional groups are useful for further reactions. Oxidation of organic compounds generally increases the number of bonds from carbon to oxygen (or another electronegative element, such as a halogen), and it may decrease the number of bonds to hydrogen.Related Products of 367-93-1

Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts