Functionalized Cyclopentenones and an Oxime Ether as Antimicrobial Agents

Abstract

Several naturally occurring cyclopentenones, such as palmenones and nigrosporiones, exhibit antimicrobial activity. Herein we describe the antimicrobial activity of cyclopentenones and derivatives that can be easily accessed from biomass derivatives furfural and 5‐hydroxymethylfurfural. Upon screening a range of functionalized trans‐diamino‐cyclopentenones (DCPs) and δ‐lactone‐fused cyclopentenones (LCPs), an oxime ether derivative of DCP was identified that exhibited remarkable antimicrobial activity against Gram‐positive bacteria, including resistant strains such as methicillin‐resistant S. aureus (MRSA) and vancomycin‐resistant E. faecalis (VRE) strains.

High-Pressure Promoted Nazarov-like Electrocyclization Enables Access to trans-4,5-Diamino-cyclopent-2-enones Bearing Electron-Poor Anilines

“…DCP 4 was isolated as a yellow solid following general procedure A (70% yield, 60.1 mg). 1 H NMR (300 MHz, CDCl 3 ): δ 7.66 (dd, J = 6.3, 2.1 Hz, 1H), 6.86–6.78 (m, 2H), 6.72–6.63 (m, 4H), 6.61–6.57 (m, 1H), 6.54 (dd, J = 6.3, 2.2 Hz, 1H), 6.17–6.06 (m, 1H), 5.29 (dt, J = 3.9, 2.1 Hz, 1H), 4.33–4.11 (m, 6H), 3.45–3.15 (m, 5H) ppm …”

“…DCP 5 was isolated as a yellow solid following general procedure A (32% yield, 29.9 mg). 1 H NMR (300 MHz, CDCl 3 ): δ 7.63 (dd, J = 6.3, 2.1 Hz, 1H), 7.08 (ddd, J = 7.7, 5.8, 1.6 Hz, 2H), 6.92–6.82 (m, 2H), 6.75–6.63 (m, 3H), 6.52 (dd, J = 6.3, 2.1 Hz, 1H), 6.29 (dd, J = 8.3, 1.2 Hz, 1H), 5.18 (dt, J = 4.0, 2.1 Hz, 1H), 4.25 (d, J = 3.7 Hz, 1H), 3.68–3.39 (m, 5H), 3.21–2.96 (m, 5H) ppm …”

“…1 H NMR (300 MHz, CDCl 3 ): δ 7.66 (dd, J = 6.3, 2.1 Hz, 1H), 6.86−6.78 (m, 2H), 6.72−6.63 (m, 4H), 6.61−6.57 (m, 1H), 6.54 (dd, J = 6.3, 2.2 Hz, 1H), 6.17−6.06 (m, 1H), 5.29 (dt, J = 3.9, 2.1 Hz, 1H), 4.33−4.11 (m, 6H), 3.45−3.15 (m, 5H) ppm. 3 trans-4,5-Bis(2,3-dihydro-4H-benzo[b] [1,4]thiazin-4-yl)cyclopent-2-en-1-one 5. DCP 5 was isolated as a yellow solid following general procedure A (32% yield, 29.9 mg).…”

Tandem Thio‐Michael Addition/Remote Lactone Activation of 5‐Hydroxymethylfurfural‐Derived δ‐Lactone‐Fused Cyclopentenones

“…[1] In this sense, and in line with one of the 12 principles of green chemistry, [2] the use of biorenewable feedstock for the production of diversified compounds is an important topic that has been tackled by several research groups. Amongst the biorenewable feedstocks, [3] furanic platform molecules such as furfural and 5hydroxymethylfurfural (HMF) are included in the top 10 + 4 biobased product opportunities [4] and have been used for the preparation of value-added chemicals as depicted in Figure 1A (e. g., photochromic systems; [5] materials; [6] fuels; [7] intermediates for total synthesis; [8] bioactive compounds including FDAapproved ranitidine; [9] drug delivery; [10] bioconjugation systems [11] ). Additionally, the reactivity of furanic platforms has been harnessed to design complex structures such as 7oxanorbornenes, triarylmethanes, pyridinium salts, and substituted cyclopentenones (CP).…”

A direct Diels–Alder reaction of chitin derived 3-acetamido-5-acetylfuran

“…materials, energy and drug discovery). 3,[5][6][7][8][9][10][11][12][13][14][15][16][17] Importantly, furfural/HMF derivatives undergo reversible DA reactions with dienophiles to yield 7-oxanorbornenes . This dynamic character has solely led to extensive research on understanding interactions and mechanistic nuances governing furan diene/dienophile DA reactions and fine-tuning of reactants to bypass the reactivity and stability of the 7-ONB products (Scheme 1A).…”