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The flavonoid composition of plants is one of the adaptive variables in their adjustment to environmental conditions [1]. Therefore, an investigation of the polyphenol composition of plants from the genus Tamarix (Tamaricaceae), which are halophytes (salt tolerant plants), is considered timely [2].This communication continues an earlier study of Tamarix elongata Ledeb. and T. laxa Will. (aerial part) that were collected in the Aral and Almaty regions during flowering [3,4]. Quantitative analysis showed 1.45 and 1.50% flavonoids, respectively.Compounds 1-9 were isolated by adsorption-distribution (silica gel, polyamide) and gel chromatography (Sephadex, LH-20) from the ethylacetate fraction and aqueous remainder.Chemical (acid hydrolysis, alkaline destruction, anthocyanidine test) and spectral (UV, IR, mass, PMR, 2D NMR HMBC spectroscopies) data and a comparison with the literature identified 1-9 as 7,3′,4′-trihydroxy-5-methoxyflavone (1), 3,7,4′-trihydroxy-5-methoxyflavone (2), 3,5,7-trihydroxy-3′,4′-dimethoxyflavone (3), kaempferide 3-O-β-glucopyranoside (4), quercetin 3-O-β-glucopyranoside (5), quercetin 3-O-sulfate (6), isorhamnetin 3-O-β-glucopyranoside (7), isorhamnetin 7-O-sulfate (8), and tamarixetin 3-O-α-rhamnopyranoside (9). Compounds 5 and 6 were isolated previously from T. hispida [3] and T. aplexicaulis [5]. Compounds 1-3 and 7-9 were isolated for the first time from plants of the genus Tamarix and the Tamaricaceae family. 7,3′,4′-Trihydroxy-5-methoxyflavone (1), mp 304-306°C. UV spectrum (MeOH, λ max , nm): 366, 267; +CH 3 COONa: 370, 270; +CH 3 COONa + H 3 BO 3 : 377, 268; +AlCl 3 : 424, 270; +AlCl 3 + HCl: 363, 268; +NaOMe: 385, 267. PMR spectrum (500 MHz, CDCl 3 , δ, ppm, J/Hz): 3.88 (3H, s, -OCH 3 ), 6.12 (1H, s, H-3), 6.27 (1H, d, J = 2.0, H-6), 6.44 (1H, d, J = 2.0, H-8), 7.70 (1H, d, J = 8.0, H-5′), 8.15 (1H, dd, J = 2.0, 8.0, H-6′), 8.24 (1H, d, J = 2.0, H-2′). Mass spectrum (EI, 70 eV, m/z, I rel , %): 300.H 12 O 6 [6]. 3,7,4′-Trihydroxy-5-methoxyflavone (2), mp 240-242°C. UV spectrum (MeOH,λ max , nm): 354, 266; +CH 3 COONa: 367, 268; +CH 3 COONa +H 3 BO 3 : 364, 267; +AlCl 3 : 423, 269; +AlCl 3 + HCl: 423, 269; +NaOMe: 375, 271. PMR spectrum (400 MHz, CD 3 OD, δ, ppm, J/Hz): 3.86 (3H, s, -OCH 3 ), 6.27 (1H, d, J = 2.0, H-6), 6.39 (1H, d, J = 2.0, H-8), 7.05 (2H, d, J = 8.0, H-3′,5′), 8.17 (2H, d, J = 8.0, H-2′,6′). Mass spectrum (EI, 70 eV, m/z, I rel , %): 300.0 (100.0), 285.2 (41.5), 135.1 (13.6), 107.1 (3.6), C 16 H 12 O 6 [7]. 3,5,7-Trihydroxy-3′,4′-dimethoxyflavone (3), mp 267-270°C. UV spectrum (MeOH, λ max , nm): 352, 260; +CH 3 COONa: 351, 268; +CH 3 COONa + H 3 BO 3 : 350, 269; +AlCl 3 : 389, 270; +AlCl 3 + HCl: 350, 266; +NaOMe: 389, 266. PMR spectrum (400 MHz, CD 3 OD, δ, ppm, J/Hz): 3.84 (3H, s, OCH 3 ), 3.88 (3H, s, OCH 3 ), 6.23 (1H, d, J = 2.0, H-6), 6.45 (1H, d, J = 2.0, H-8), 7.06 (1H, d, J = 8.0, H-5′), 7.65 (1H, d, J = 2.0, H-2′), 8.24 (1H, dd, J = 2.0, 8.0, H-6′). Mass spectrum (EI, 70 eV, m/z, I rel , %): 330.0

Oral cancer (OC) is the eighth most common cancer, particularly prevalent in developing countries. Current treatment includes a multidisciplinary approach, involving chemo, radio, and immunotherapy and surgery, which depends on cancer stage and location. As a result of the side effects of currently available drugs, there has been an increasing interest in the search for naturally-occurring bioactives for treating all types of cancer, including OC. Thus, this comprehensive review aims to give a holistic view on OC incidence and impact, while highlights the preclinical and clinical studies related to the use of medicinal plants for OC prevention and the recent developments in bioactive synthetic analogs towards OC management. Chemoprophylactic therapies connect the use of natural and/or synthetic molecules to suppress, inhibit or revert the transformation of oral epithelial dysplasia (DOK) into oral squamous cell carcinoma (OSCC). Novel searches have underlined the promising role of plant extracts and phytochemical compounds, such as curcumin, green tea extract, resveratrol, isothiocyanates, lycopene or genistein against this malignancy. However, poor bioavailability and lack of in vivo and clinical studies and complex pharmacokinetic profiles limit their huge potential of application. However, recent nanotechnological and related advances have shown to be promising in improving the bioavailability, absorption and efficacy of such compounds.Keywords: oral cancer; head and neck squamous cell carcinoma; phytotherapy; curcumin; green tea extract; bioavailability; nanotechnology cancer stage and location. Ideally, it comprises a multidisciplinary approach involving chemotherapy, radiotherapy, immunotherapy and surgical removal of the tumor or their combination, often accompanied by severe side effects [9].

Over 700 species of plants belonging to one group or another of halophytes are indigenous to saline soils of the arid zone of Central Asia. Representatives of the Chenopodiaceae and Tamaricaceae families are euhalophytes and are among the most numerous species in the flora of saline soils [1].Camphorosma monspeliacum L. (Chenopodiaceae) is known to be a source of essential oil [2] and an alkaloid [3]. However, other groups of natural compounds have been insufficiently studied.The plant is used in folk medicine to treat lung diseases and as a stimulant, diuretic, and sudorific [4].We have initiated an investigation of the MeOH extract of the aerial part of C. monspeliacum collected in Almaty District during flowering. Chromatography (PC, TLC) using specific developers detected flavonoids; coumarins; alkaloids; amino, phenolic, and fatty acids; carbohydrates; and triterpenoids. The MeOH extract was worked up successively with CHCl 3 , EtOAc, and n-BuOH. Adsorption-distribution chromatography of the EtOAc fraction over silica gel (CHCl 3 :MeOH) and polyamide (MeOH:H 2 O) isolated compounds 1-5.The structures of the isolated compounds were established by chemical (acid hydrolysis, alkaline destruction, anthocyanidine test) and spectral methods (UV, mass, PMR, 13 C NMR, and 2D NMR spectroscopies) and by comparison with the literature.The attachment sites of the carbohydrate units were determined by 2D heteronuclear correlation spectroscopy HMBC and UV spectroscopy with ionizing and complexing reagents. Compounds 1-5 were isolated for the first time from a plant of the Camphorosma genus. Isorhamnetin (3,5,7,4′-tetrahydroxy-3′-methoxyflavone) (1), mp 304-305°C (MeOH). PMR spectrum (300 MHz, CD 3 OD, δ, ppm, J/Hz): 3.94 (3H, s, OCH 3 ), 6.18 (1H, d, J = 2.0, H-6), 6.38 (1H, d, J = 2.0, H-8), 6.75 (1H, d, J = 8.0, H-5′), 7.65 (1H, dd, J = 2.0, 8.0, H-6′), 7.73 (1H, d, J = 2.0, H-2′). Mass spectrum (EI, 70 eV, m/z): 316, C 16 H 12 O 7 [5]. Isorhamnetin-3-O-β-D-glucopyranoside (2), mp 198-200°C (70% CH 3 OH). UV spectrum (MeOH, λ max , nm): 346, 256; +CH 3 COONa: 355, 268; +CH 3 COONa + H 3 BO 3 : 355, 261; +AlCl 3 : 433, 275; +AlCl 3 + HCl: 396, 270; +NaOMe: 400, 275. PMR spectrum (400 MHz, CD 3 OD, δ, ppm, J/Hz): 3.90 (3H, s, OCH 3 ), 6.20 (1H, d, J = 2.0, H-6), 6.30 (1H, d, J = 2.0, H-8), 6.80 (1H, d, J = 8.0, H-5′), 7.52 (1H, dd, J = 2.0, 8.0, H-6′), 7.80 (1H, d, J = 2.0, H-2′), 4.90 (1H, d, J = 7.0, H-1′′), 3.50-3.30 (6H, m, H-2″, H-3″, H-4″, H-5″, H-6″). Mass spectrum (EI, 70 eV, m/z): 478; C 22 H 22 O 12 [6]. Isorhamnetin-3-O-β-D-galactopyranoside (3), mp 210-211°C (70% CH 3 OH). UV spectrum (MeOH, λ max , nm): 334, 252; +CH 3 COONa: 331, 270; +CH 3 COONa + H 3 BO 3 : 334, 252; +AlCl 3 : 403, 275; +AlCl 3 + HCl: 400, 276; +NaOMe: 400, 275. PMR spectrum (600 MHz, CD 3 OD, δ, ppm, J/Hz): 3.94 (3H, s, OCH 3 ), 6.14 (1H, d, J = 2.0, H-6), 6.39 (1H, d, J = 2.0, H-8), 6.68 (1H, d, J = 8.0, H-5′), 7.31 (1H, dd, J = 2.0, 8.0, H-6′), 7.33 (1H, d, J = 2.0, H-2′), 5.28 (1H, d, J = 7.7, H-1″), 3.88 (1H, dd, J = 10.0, 7.0, H-2″),...