A fresh chloro-trinoreremophilane sesquiterpene 1, three fresh chlorinated eremophilane sesquiterpenes 2C4, having a known compound collectively, eremofortine C (5), were isolated from an Antarctic deep-sea derived fungus, sp. deep ocean, the aforementioned intense conditions arranged the manifestation of uncommon biosynthetic systems that can lead to exclusive supplementary metabolites [3]. Undeniably, the exploitation of the peculiar metabolic pathways represents a fresh chance for the finding of bioactive supplementary metabolites [4]. Therefore, the study community continues to be urged to explore the untapped metabolic tank from deep-sea fungi to be able to fight human illnesses [5]. Inside our efforts to find novel energetic compounds through the supplementary metabolites of deep-sea produced microorganisms [6,7,8], a fungi, defined as sp. PR19N-1, was from a deep-sea sediment gathered in Prydz Bay (?1000 m). Its draw out exhibited brine shrimp lethality activity. Research on the energetic constituents of this fungus led to the isolation of four new chlorinated eremophilane sesquiterpenes 1C4, along with a known compound, eremofortine C (5) [9,10] (Figure 1). Herein, we describe their isolation, structure elucidation and in Semaxinib vitro cytotoxicity evaluation. Open in a separate window Figure 1 Structures of compounds 1C5. 2. CD123 Results and Discussion Compound 1 was obtained as an optically active colorless oil. The molecular formula of C14H15ClO4 was established through HRESIMS data ([M + Na]+ 305.0543, calcd. 305.0557), indicating seven double bond equivalents. The IR spectrum showed absorption bands characteristic for hydroxyl, carbonyl and double bond moieties at 3292, 1731, 1634 cm?1, respectively. One-dimensional NMR data (Table 1, Table 2) unveiled 8 sp2 deshielded carbons (1 OC=O, 3 CH=C, 1 C=O), and 6 sp3 shielded carbons (3 CH3, 2 CH, 1 C), indicating the presence of two rings in the molecule. The two fused six-membered rings were defined by extensive analysis of HMBC cross peaks from the diagnostic methyls H3-11 to C-4, C-5, C-6 and C-10, H3-12 to C-3, C-4, Semaxinib C-5, as well as from the olefinic protons H-2 to C-1, C-3, C-4, and C-10, H-6 to C-4, C-5, C-8, C-10, and C-11, and H-9 to C-1, C-5, C-7, and C-10. Extensive analysis of MS and NMR data led us to a trinor-eremophilene core with an 8-oxo-1(2),9(10)-diene unit [11,12]. The hydroxyl group attached to C-7 was positioned using HMBC correlations (Figure 2) between the exchangeable proton (OH-7) and C-6, C-7 and C-8. In addition, an acetoxy group was assigned to C-3 via HMBC correlations between H-14 and C-13, and between C-13 and H-3. Furthermore, the COSY-defined spin program H-2/H-3/H-4/H3-12 combined with the insufficient an olefinic proton sign at C-1 in the HMQC range indicated the positioning of the chlorine atom at C-1. Desk 1 13C NMR data for substances 1C4 (150 MHz, ppm). in Hz). 299.1060 (calcd. 299.1050). Crucial 1H and 13C NMR resonances (Desk 1, Desk 2), for the shielded methyl groupings at H 1 especially.04 (= 7.0 Hz) and H 1.20, led us to consider an eremophilane-type sesquiterpene skeleton for 2. The current Semaxinib presence of an epoxide moiety with 13C peaks at C-7 (C 61.8) and C-11 (C 67.3) was suggested in comparison from the 13C NMR range with those of 5a [9,10], and was confirmed by HMBC correlations (Body 2) from H-13 to C-7, C-12 and C-11, from H2-6 to C-7, C-10, C-14 and C-11, and from H-12 to C-7, C-13 and C-11. Based on the 1HC1H COSY relationship between 12-OH and H2-12, the only real primary alcohol was located at C-12. Thus, the above mentioned evidence recommended 2 and 5a got the same substructure b (Body 1) [9,10]. Cautious analysis from the NMR data of 2 indicated the band A was equivalent compared to that in substance 1. The primary differences of these had been the 3-acetoxy group Semaxinib changed by 3-OH that was verified by COSY correlations of H3-15/H-4/H-3 (Body 2) and chemical substance change at C-3 (C 66.9) in 2. The settings of H-3 and H-4 was designated according with their distributed coupling continuous (3269/271 (rel. 3:1), as well as the HRESIMS resulted in the molecular formulation C15H21ClO2 (exp. 269.1312, calcd. 269.1308), in keeping with five levels of unsaturation. The IR range showed the current presence of hydroxyl, carbonyl and dual bond moieties, exhibiting characteristic absorption rings at 3418, 1715, 1656 cm?1, respectively. The 1H and 13C NMR resonances (Desk 1, Desk 2) of 3 had been similar to the known eremophilane-type sesquiterpenes that possessed an 8-oxo-7(11),9(10)-diene products [17,18]. The related HMBC correlations had been.