Phytochemistry Letters 41 (2021) 139–141 1874-3900/© 2020 Phytochemical Society of Europe. Published by Elsevier Ltd. All rights reserved. Two new dihydrofavonols from the leaves of Artocarpus scortechinii King Norzafneza Mohd Arriffn, Shajarahtunnur Jamil *, Norazah Basar Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor, Malaysia A R T I C L E INFO Keywords: Artocarpus scortechinii Moraceae Dihydrofavonol Flavonoids ABSTRACT Two new dihydrofavonols named as artoscortonol A (1) and artoscortonol B (2), along with fve known com- pounds, macakurzin C, femichapparin A, apigenin, luteolin and β-sitosterol were isolated from the leaves of Artocarpus scortechinii King (Moraceae). All of the structures were elucidated and confrmed by spectroscopic analysis and comparison with the literature review. This is the frst report on the isolation of phytochemicals from the leaves of A. scortechinii King. 1. Introduction The genus Artocarpus belongs to the family of Moraceae comprises approximately about 50 species. This genus can be found in South-East Asia, New Guinea and Southern Pacifc. These plant are evergreen and deciduous with all parts contain white latex (Jagtap and Bapat, 2010). Artocarpus had been well known due to the edible fruits and useful as timber. This genus also possesses therapeutic properties that can treat various human diseases such as anaemia, asthma, dermatitis, skin dis- eases and toothache (Hakim, 2010). Most of Artocarpus species produce favonoids, terpenoids and stilbenoids, which had been reported to show antioxidant (Lathiff et al., 2015), antimicrobial (Jamil et al., 2014), cytotoxic (Musthapa et al., 2009), antityrosinase (Jamil et al., 2014) and acetylcholinesterase inhibition activities (Shah et al., 2016). Artocarpus scortechinii King an endemic plant in Malaysia and locally known as terap hitam. This species have similarity with A. elasticus (terap nasi). The difference with A. elasticus is on the stem which is darker while the leaves are not too large and wide. This plant can be found scattered throughout Malaysia in lowland forest, and Sumatra, Indonesia (Kochummen, 1978). To date, there is no report on the isolation of phytochemicals from the leaves of A. scortechinii. In continuation of our phytochemicals and biological activity studies on this genus (Arriffn et al., 2015, 2017), herein we report the isolation and identifcation of the new dihydro- favonols from the leaves of A. scortechinii King (Fig. 1). 2. Results and discussion Compound (1) was isolated as yellow powder with specifc rotation value of [α] 25 D 14.9 ◦ (c 0.03, CH 3 COCH 3 ). The HRAPCIMS spectrum revealed the molecular ion peak at m/z 339.1227 (calculated m/z 339.1230) which consistent with the molecular formula of C 20 H 18 O 5 . It was in agreement with the degree of unsaturation value of 12. The IR spectrum revealed the absorption bands for hydroxyl group (3479 cm 1 ), sp 3 CH stretching (2923 cm 1 ), chelated carbonyl group (1631 cm 1 ), aromatic CC (1472 and 1586 cm– – 1 ) and CO– stretching (1270 cm 1 ). The 1 H NMR (Table 1) displayed the signals for a pair of ortho- coupled olefnic protons at δ 5.50 (d, J =10.0 Hz, H-10) and δ 6.52 (d, J =10.0 Hz, H-9). An ABX spin system were observed at δ 5.12 (d, J =11.6 Hz, H-2), δ 4.55 (dd, J = 11.6 and 1.6 Hz, H-3) and δ 3.54 (1H, d, J =1.6 Hz, 3OH) at ring C. Two singlet signals at δ 1.45 and δ 1.48 were assigned for H-12 and H-13 respectively. A singlet signal for an isolated aromatic proton was observed at δ 6.07 for H-8 at ring A. A multiplet signal was also observed between δ 7.49–7.58 which attributable for H- 2 ′ -H-6 ′ at ring B. The scalar coupling of all protons in (1) i.e H-2/H-3, H- 9/H-10 and protons at ring B (H-2 ′ -H-6 ′ ) were confrmed by the COSY analysis (Fig. 2). The 13 C NMR spectrum (Table 1) showed the total of twenty signals corresponding to twenty carbons in the structure. The methine carbons were assigned based on the HMQC spectrum which showed the direct connectivity between protons to carbons. The spectrum revealed the connectivity between proton at δ 4.55 (H-3) to carbon at δ 72.4 (C-3). In addition, proton at δ 5.12 (H-2), δ 5.50 (H-10), δ 6.07 (H-8), and δ 6.52 (H-9) were seen direct connected to carbons at δ 83.3 (C-2), δ 126.8 (C- 10), δ 98.0 (C-8), δ 115.2 (C-9), respectively. The spectrum also showed direct connectivity signals at δ 7.49 (H-3 ′ -5 ′ ) to δ 128.7 (C-3 ′ /5 ′ ) and 7.58 (H-2 ′ /6 ′ ) to δ 127.5 (C-2 ′ /6 ′ ). Comparison of the 13 C NMR and DEPT 45 disclosed the presence of eight quaternary carbons (Table 1). * Corresponding author. E-mail address: shajarah@utm.my (S. Jamil). Contents lists available at ScienceDirect Phytochemistry Letters journal homepage: www.elsevier.com/locate/phytol https://doi.org/10.1016/j.phytol.2020.11.010 Received 29 August 2020; Received in revised form 16 November 2020; Accepted 19 November 2020