Lupine Publishers | Comments on Whether or Not Traditional Chinese Medicine and Acupuncture are Pseudosciences

 Lupine Publishers | LOJ Pharmacology & Clinical Research

Abstract

Whether or not the traditional Chinese medicine (TCM) and acupuncture are science remains controversial. It seems that both should not be judged with the criteria based on the deductive reasoning because it goes beyond doubt that the different logical reasoning models between the East and the West need more conversation. Issues affecting the efficacy of TCM and acupuncture like Collection, Processing, Acupuncture as part of the health system, Designing Pattern-based research, Locating acupoints accurately, and Proper prescriptions are presented for discussion for the modernization and the scientization of TCM and acupuncture.

Keywords: Inductive/Deductive Reasoning; Acupoint; Yin-Yang; Pattern Identification

Introduction

Acupuncture and the traditional Chinese Medicine (TCM) are complex, developed with the philosophical principles and reflecting Chinese thought, which is used to place the human body into a large system through the observation of nature and has been recognized and practiced totreat various diseases and symptoms worldwide. It’s been argued academically and clinically for long whether or not the TCM and acupuncture should be treated as science or pseudoscience. The Chinese are used to the inductive reasoning for more than five thousand years, compared to deductive reasoning of in the West. Based on this reasoning model, the TCM and acupuncture features similarities with Yin-Yang, Qi-Blood, the Five Elements, and Pattern identification in theories. In addition to the scientific evidence with modern techniques, such as fMRI and CT, to examine the effects of the TCM and acupuncture, it seems to suggest that some key issues deserve attention. Having the better understanding and learning of the TCM and acupuncture, which will greatly promote research in the TCM and acupuncture, may be beneficial to modernization and scientization of the TCM and acupuncture and rethinking the definition of science.

Current Issuess

Collection

The clinical use of Chinese herbs must follow the TCM theories and be based on the patient’s specific conditions with accurate diagnosis, following the principles of pattern identification. Ban-xia (Pinellia ternate) is effective to drain phlegm caused by dampness. Ban literally in Chinese means in the middle summer of which indicates the best harvest time is in the mid-summer between May 6 (lixia,) when summer begins and June 21, maximum summer (xiazhi) for the maximum constituents and best quality. However, this rule seems to be difficult to follow, suggesting why the efficacy is as good as expected for the clinical outcomes [1].

Processing

In order to facilitate the use of Chinese herbs to meet the clinical needs, herb processing is required because it can generally reduce toxicity, alter energetic nature, and reinforce efficacy to increase the therapeutic effectiveness. Radix Bupleuri (RB) bearing the properties of spicy, cool, and bitter is one of the most popular traditional Chinese medical herbs to treat Liverrelated diseases. Radix Bupleuri is derived from the dried roots of Bupleurum scorzonerifolium Willd (Nan Chaihu) and Bupleurum chinense DC. (Pei Chaihu), which is the main ingredient of the most frequently used preparations Da Chai Hu decoction and Xiao Chai Hu decoction in the Treatise on Injury by Cold (Shang Han Lun). The major differences between Bupleurum scorzonerifolium and Willd Bupleurum chinense DC. are the indication of Bupleurum chinense DC. is to disperse stagnated Liver qi while Bupleurum scorzonerifolium Willd is used to reinforce Yang Qi in the pattern of Middle Jiao deficiency [1]. However, whether or not Bei Chaihu (Bupleurum chinense DC.) is selected as the components of these two formulas remains uncertain since it is not specified by the author Zhang Zhongjing of Treatise on Injury by Cold (Shang Han Lun), even though Bupleurum chinense DC. is mostly selected for clinical use. On the other hand, the evidence-based researcher shows the levels of neurotransmitters in the frontal cortex and hippocampus can be regulated significantly with the use of vinegarbaked Bupleuri Radix In addition, vinegar-baked Bupleuri Radix can be more effective for relieving the depressed Liver qi and bring about the better antidepressant effect than unprocessed Bupleuri Radix [1,2].

Acupuncture as Part of The Health System

Whether or not acupuncture is science remains controversial only because this issue is presented and discussed by those who are used to the deductive reasoning. However, the objective evidence of the population of China has given the answer, explaining the statuses of TCM and acupuncture in China and the Chinese communities around the world. TCM and acupuncture had been the major approaches in the health system in the ancient China until the Qing dynasty. In the first half of the nineteen century, the population of China accounted for one-third of the world population even though China had been tortured by the twenty one major wars and battles, leading to the fluctuation of population. It is estimated the population was about forty two million in the Qin dynasty (221- 206 BC) and increased to eighty six million in the Han dynasty (206 BC- 220 AD). The population moved around 100 million to 150 million until 1700s after the Ming dynasty (1368-1344) and earlier period of the Qing dynasty (1644-1912). More impressive evidence is that the population doubled in a century in the period between 1749 and 1851[3,4].

Designing Pattern-Based Research

It is noted that most of the contemporary scientific researches examining the efficacy of acupuncture and TCM only focuses on diseases, instead of following the pattern identification. It is understood that a disease refers to the loss of the balance of YinYang [3]. TCM and acupuncture see the body as a miniature of the universe in diagnosis and treatment and believe the body acts with the universe, which is totally different from the Western medicine. Yin and Yang are the philosophical concepts and abstract with the functions broader than the anatomical knowledge of the Western medicine. On the other hand, TCM emphasizes the congenital constitution passed from the parents, which is equivalent to the concept of gene centered in the Precision medicine [5]. It is agreed that criteria for evaluating Pizza should not be used to assess Burrito. In other words, the research designs not following the pattern identification cannot accurately exemplify the TCM and acupuncture theories to a great extent because they are breaking the rules and principles developed with the inductive reasoning model [6].

Locating Acupoints Accurately

How to accurately locate an acupoint is the key to the successful treatment. For, example, LIV1 (Da Dun) is the most commonly used acupoint in the acupuncture treatment for regulating Qi in the lower jiao and Liver qi to alleviate pain. Unfortunately, whether this acupoint is located on the dorsal aspect of the big toe, at the junction of lines drawn along the lateral border of the nail and the base of the nail, approximately 0.1 cun from the corner of the nail [7] or on the lateral side of the terminal phalanx of the great toe, 0.1 cun from the corner of the nail [8] remains controversial in the clinical practice and textbooks.

Proper Prescription

As discussed above, Pattern identification is vital for the successful treatment outcomes. The historical developments show that an acupuncturist may face the following challenging issues, such as only selecting traditional acupoints for use, only selecting extra acupoints, or the combinations of traditional acupoints with extra acupoints, while a TCM practitioner needs to consider the processed/unprocessed herbs, the collection way of the herbs. Up to now, there has not scientific evidence to show which choice can reach the best treatment outcomes. In other words, these issues depend on acupuncturists’ wisdom and experience.

Discussion

There has not been sufficient scientific evidence to prove the meridians exist. However, acupuncture is recommended by the WHO [8] and widely known for the effectiveness in the treatment of pain. Current development and the acceptance of acupuncture in the West may suggest whether or not the definition of science can apply to the acupuncture and the TCM still deserves attention and discussion. The efficacy in reducing pain is one of the main reasons why it has been recognized to be the effective approach around the world. The plentiful evidence on the effects of acupuncture on specific painful conditions has been presented. The systematic review of 13 trials of acute pain found that acupuncture is more effective than both sham needling and painkillers [9-11]. Banxia (Pinellia ternate) is used to drain phlegm effectively caused by dampness, which suggests that it should not be selected to fight against phlegm caused by dryness. This example highlights the importance of pattern identification for the optimal and bestoutcomes. In addition, the nature of the Chinese herbs is changed when it is processed, which indicates how to identify accurately the characteristics of Chinese herbs is crucial to the clinical use. The historical developments show that there are challenges ahead of the TCM and acupuncture learners and practitioners, such as whether it is effective to select the unprocessed herbs, research design following the pattern identification, only use acupoints on the traditional regular meridians, when to combine the regular acupoints with the extra acupoints, how to decide the accurate needling duration, etc.

Conclusion

The expected treatment and experiment outcomes will not occur until the acupuncture and TCM patterns are followed and taken into the consideration since there exist some fundamental differences between the Western medicine and the TCM, including acupuncture. On the other hand, it deserves attention that whether the definition of science developed with deductive reasoning can apply to the Yin-Yang and the Five Elements theories derived from the inductive reasoning needs more discussion.

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Lupine Publishers | A Mini Review: Seaweeds Negotiate a Vital Risk Factor of Cardiovascular Disease

 Lupine Publishers | Pharmacology & Clinical Research

Abstract

The high blood cholesterol level is one of the major risk factors of coronary heart disease. The total lipid includes total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglycerides. The high-density lipoprotein cholesterol is good for the heart health; the high level of the high-density lipoprotein cholesterol is helpful to our health. But the high level of the low density lipoprotein cholesterol is responsible for gradual deposition of cholesterol along the inner wall of arteries which followed some serial change to develop atherosclerosis and blockage in the arteries to promote the development of cardiovascular pathogenesis which is consider also the major risk factor for heart failure. The low-density lipoprotein cholesterol value should be below 100mg/dL. The low-density lipoprotein cholesterol level sometimes become high in our body due to uptake of the high amount of food with saturated and trans-fat. The food habit in different parts of the world is not adequate to prevent and reduce the health hazards and hence it is believed that food habit is the basic reason for the major health problems such as cardiac disease, obesity, diabetes, hepatic disorder and related diseases for global populations. Research shows appropriate fatty acids composition of some marine macro algae is very useful to prevent cardiovascular disease development. Likewise, marine macro algae are composed of adequate amount of proteins, carbohydrates, fatty acids, peptides, minerals, vitamins, long chain molecules, hydrocolloids which will also negotiate nutritional deficiencies for uptake marine macro algae as food items or food ingredients. So, marine macro algae may be use as cardio-protective biomedicine in future after detailed analysis and critical evaluation. The fatty acids compositions and the cholesterol lowering activity of some seaweed are discussed in brief.

Keywords: Cholesterol; Low density lipoprotein Cholesterol; Saturated fat; Marine macro algae; Cardio protective

https://lupinepublishers.com/pharmacology-clinical-research-journal/pdf/LOJPCR.MS.ID.000112.pdf

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Lupine Publishers | Synthesis of New Oxazin Compounds Derived from Furfural, Chalcons and Schiff Bases

Abstract

Oxazine compounds have been succeeded to be used for versatile applications in various area of pharmacy, medicine and other biological uses such as Antiplatet aggregation activity, antidiabetic ,antidepressant activity ,In the investigation some new oxazine compounds have been synthesized using different routes [1]. The oxazine (A2-6) were prepared from the corresponding chalcone compounds (A1-6)by treatment of ethyl urea with these chalcones. oxazine (A5-8)were prepared from the cyclization of the corresponding compounds (A4-7) by formaldehyde compounds (A4-8 )themselves were prepared by reduction of Schiff bases (A3- 7) using NaBH4 .The third series of oxazines (A6-9)were synthesized by the reaction of furfural with hydroxyl Aromatic Compounds in methanolic ammonia. The synthesized compounds were studied by IR spectroscopy and are discussed [2].

Keywords: Oxazines; Furfural; Chalcones; Schiff bases

Introduction

Oxazine compounds were first synthesized from malonyl chloride and some aliphatic and aromatic ketones1. These oxazine compouds were also synthesized by self-condensation of malonyl chloride with nitrile componds2. Butt, Elivdge and foster found that condensation of malonyl chloride with isocyanates results into the formation of the corresponding pyrano oxazine derivatives 3. Ried, Ninninger and Bats have prepared pyrano oxazines from the condensations of malonyl chloride with thiocyanates 4. Some of the synthesized compouds showed anticancer activities5. There are a lot of methods in the literature for the preperation of benzoxazine compouds including. ring expantion methods 6, [3] oxidation of 2-isopropyl indole with monoperphthalic acid 7 Intramolecular rearrangment8 iso cyanate precursors9 antharanilic acid precursor 10,N-acylantharanilc acid11, from chalcones precursors12-14 and recently pd-catalyzed carbonylation of 1-azido-2-iodobenzene15.these oxazine componds have proved to have significant effect as thrombin inhibitor16 potassium modulator17, antiplatelet18,inhibitory activity toward human leukocyte elastase(HLE)19 and many other biological and medical uses 20-22 .In our investigation and according to the above importance of this type of compounds we choose antharanilic acid, chalcon and Schiff bases as precursors for the synthesis of new series of oxazine compounds ,in an attempt to study their possibility to be used as drugs which is our next work [4-8].

 

Experminta

All melting point were uncorrected using electro thermal melting point apparatus type SMP30 U. K, IR spectra were recorded using FTIR spectrophotometer type Bruker Alpha (ATR). All chemical were supplied by Fluke, Sigma-Aldrich companies. 2-Acetylbenzimidazole was prepared according to the published procedure22 [9-12].

Synthesis of Benzimidazoyl Chalcones (A1-6)

2- Acetyl-benzimidazole compound was prepared by chromic acid oxidation of the corresponding alcohol following the same publisher procedue23 Its structure was checked by IR and melting point in comparison with the published one .This compound was allowed to react with equimolar amount of some aromatic aldehyde following similar procedure 21 [13-18].

General Procedure

2- Acetyl-benzimidazole (0.01mol.) was dissolved in (30ml) from Ethanol and (30 ml) of water then10% sodium hydroxide solution (3ml) was added drop-wise to the reaction mixture, the mixture stirred for( 1h. ) then (0.01mol) of aldehyde was added to the mixture with continuous stirring for (3-5h) .the solid was filtered off and recrystallized from ethanol/water [19-24].

Synthesis of 4-Benzimidazoyl-6H-2-Ethylamino 1,3-Oxazines(A2-6)

General Procedure

Amixture of chalcone (0.02mo.l),urea(0.02mol.) were dissolved in ethanolic solution of sodium hydroxide(30ml).The reaction mixture was stirred for( 3-4h) with magnetic stirre, it was then poured on 20ml of cold water with stirring for 1h.then kept in refrigerator for 24h. the ppt was filtered off and recrystallized from ethanol [25,26].

Synthesis of Schiff bases(A3-6)

General Procedure

Substituted Benzaldehyde (0.01 mol.) and substituted aniline (0.01 mol.) was dissolved in methanol (15ml) and two drops of acetic acid and refluxed for (3 h.). The resulting solution was cooled and poured in cold water. The separated solid was filtered, washed with water and crystallized from ethanol.

General Procedure for the Hydrogenation of Schiff bases(A4-7)

Each Compound of (A4-7) (0.01mol.) was dissolved in methanol (15ml.) and sodium borohydride(0.015mol.) was added in small portions with stirring within 10 minutes. The reactions mixture was kept at room temperature for (1 h.). The solid separated on evaporation of most of the solvent was filtered off, washed with water and crystallized from ethanol.

Synthesis of 3,4-Dihydro-3-Aryl-2H-Naph[2,1-e] [1,3] Oxazines:(A5-8)

General Procedure

Any compound of(A3-7), (0.01mol.) and formaldehyde (0.015mol.) was dissolved in ethanol and refluxed in a water bath for 3 hours. The solid separated on cooling was filtered and crystallized from ethanol.

Synthesis of 1,6-Bis Furyl -3,2-and4,3--Aryl-1,3-Oxazines(A6-9)

General Procedure

Aromatic hydroxy compound (0.01 mol) in methanol (10ml) was added to Furfural and 10ml of 30% methanolic ammonia .the final mixture was left to stand at room temperature for 3-4 days during which the crystalline product was separated out .The crude product was filtered off ,washed with cold methanol and was recrystallized from minimum amount of methanol (Figures 1-3).

Results and Discussion

Chalcone compounds (A1-7) were synthesized from the corresponding 2-acetyl benzimidazole and some aromatic aldehydes as shown in scheme 1.

1-(benzimidazoyl-2-yl)-3-phenyl-2-propene-1-one

Yellowish- white, mp.12-145⁰C, yield83.58%, IR (neet sample Cm^-1): 1653 for C=C, 1501,1507,1584 for C=C Ar,1653 for C=N,1706 for –C=O,3241 for- NH.

1-(benzinidazoyl-2-yl)-3-(4-hydroxy phenyl)-2-propene-1- one

Black Crystals, mp.,265⁰C, yield79.55%, IR neet sample Cm^-1): 1366 for C-O,1552 for C=C Ar,1643 for C=N, 3188 for NH.

1-(benzimidazoyl-2-yl)-3-(2-bromophenyl)-2-propene-1-one

Yellow mp.216-218⁰C, yield86.3%, IR (neet. Cm^-1): 1326.19 for C-N,1475,1514,1587 for C=N, C=C Ar.,1655 for-C=O,3259 for NH.

1-(benzimidazoyl-2-yl)-3-(4-dimethylamino)-2-propene-1-one

Orange Crystals mp.125-127⁰C, yield90.33%, IR (neet. Cm^-1): 1341.28 for C-N,1519,1589 for C=C Ar,1665.93 for C=O, C=N 2971.35 for CH, 3281 for NH.

1-(benzimidazol-2-yl)-3-(2-methoxy phenyl)-2-propene-1-one

Yellowish-Green mp.196-198⁰C, yield 54,33%, IR (neet. Cm^-1): 1206,1236 for C-O,1366 for C-N,1470,1513,1574 for C=C Ar., 1647 for C=N,1699 for –C=O,1322 for NH.

1-(benzimidazol-2-yl)-3-(4-nitrophenyl)-2-propene-1-one

Yellow crystals mp 101-103⁰C, yield78.3 %, IR (neet. Cm^-1): 1333 for C=N, 1209,1512 for NO2 sym and asym., ,1590 for C=C Ar., 1654 for C=C, C=N,1698 for C=O,3113 for -NH.

1-(benzimidazol-2-yl)-3-(2-chlorophenyl)-2-propene-1-one

Yellow Crystals mp.212-4⁰C, 90.3% yield, IR (neet. Cm^-1): 1501,1584 for C=C Ar,1653 C=C, C=N,1766 for –C=O,3241 for –NH.

Oxazines from Chalcones

The above compounds were synthesized from the corresponding chalcones with ethyl urea as stated above the IR data were in agreement with similar published one12,13

6-(Benzimidazol-2yl)-2-Ethylamino-4-Phenyl-4H-1,3-Oxazine-4H-1,3-Oxazine

White solid crystals mp.193-196⁰C published:193-194 oC yield 90%.IR (neet. r Cm^-1): 1501,1507,1587 Ar C=C, 1653 C=N, 3240.75 N-H.

6-(benzimidazol-2yl)-2-ethylamino-4-(4-hydroxy phenyl -4H-1,3-Oxazine

Brownish Crystals, mp 36-38⁰C, yield 85% IR (KBr, Cm^-1).

6-(benzimidazol-2-yl)-2-ethylamino-4(2-bromo phenyl)-4H-1,3-Oxazine)

Yellow crystals, mp. 206-209⁰C, yield 91%, IR (neet. Cm^-1): 1270,1206 for C-O, 1326.19 for C-N,1513,1587 for C=C Ar., 1654 for C=N , 3264 for NH.

6-(benzimidazol-2-yl)-2-ethylamino-4-(4-dimethylamino phenyl)-4H-1,3-Oxazine

Orange crystals, mp.178-180⁰C, yield 90%, IR (neet. Cm^-1): 1216,1333 for C-O, 1512,1576 Ar C=C,1341 for C-N,1638 for C=N,3257 for NH.

6-(benzimidazol-2-yl)-2-ethylamino-4-(2-methoxy phenyl)-4H-1,3-Oxazine

Yellowish-white crystals, mp 188-191⁰C, yield 87%, IR (neet. Cm^-1): 1236.22,1322.36 for C-O sym and asym.,1322.36 for C-N, 1513.27,1574 for C=C Ar., 1647 for C=N, 3247.72 for NH.

6-(benzimidazol-2-yl)-2-ethylamino-4-(4-nitrophenyl)4H-1,3-Oxazine

Brown crystals, mp.205-207⁰C, yield 92%, IR (neet. Cm^-1): 1215,1333 for C-O,1216 for sym.NO2,1512.5 for asym.1333 for C-N,15190,1576 for C=C Ar., 1652 for C=N,3257 for NH.

6-(benzimidazol-2-yl)-2-ethylamino-4-(2-chlorophenyl)4H-1,3-Oxazine

Yellowish-white crystals, mp 201-203⁰C, yield 87%, IR (neet. Cm^-1): 1273,1325 for C-O, 1325.90 for C-N, 1476,1504,1585 for C=C Ar. 1652 for C=N,3257 for NH.

Schiff Bases(A3-6)

The above Schiff bases were synthesized by treatment of 2-hydroxy naphthaldehyde with some amines see scheme 2. These compounds were characterized by the Main IR bands as below;

2-Hydroxy Naphylidine-1- Naphthyl Amine

Deep brown crystals, mp.182-185⁰C, IR (neet. Cm^-1):1605 For C=Car .and C=N,1330for C-O,3440 for- OH.

2-hydroxy naphylidine-2-thiozolyl amine

Yellow rystals, mp.158-160⁰C, yield 88% IR (neet. Cm^-1):740.37 for C-S,1458.98,1468.96 for C=C Ar.,1128,1219 for C-O,1604for C=N,3009,3273.59 for C-H,3558 for –OH.

2-hydroxy naphylidine-2-benzothiazol-2-yl amine

 Oarrange crystals mp.196-199⁰C, yield68.9%, IR (neet. Cm^-1):737.08 for C-S,1139,1306 for C-O, 1139,1306.3 for C-O,1548.68, 1463.89 for C=CAr. 1596 for C=N,3410 for –OH.

2-hydroxy naphylidine-2(4-methyl pyridine-2-yl) amine

Yellowcrystals, mp.177-179⁰C, yield 69%, IR (neet. Cm^-1):1126,1276 for C-O,1599,1528,1480.5 for C=C Ar,C=N,3026for C-H,3363 for- OH.

Schiff Bases Reduction, The Synthesis of Arylamino Naphthos(A4-7)

Schiff bases reduction was accomplished byNaBH4 at room temperature as stated in the experimental part see scheme 2. The reaction with this reagent cause to color change of the colored Schiff bases into white or faint colored products.

1-Naphthyl amino methyl 2- naphthol

Brownish yellow crystals, mp.86-92⁰C, yield 83.4%, IR (neet. Cm^-1):759.99for NH def.,1257,1357 C-O,1466,1516,1580 C=C Ar.,3042.7 CHstr.,3326.7 NH, 3542 for OH.

2-Thiazol-2-yl amino methyl-2-naphthol

White crystals, mp.193-196⁰C, yield 89.3%, IR (neet. Cm^-1): 7443,812.36 for NH def.,1215,1270,1339.94 C-O,1443, 1540,1597.8 for C=C Ar. ,3009CH,3272NH,3488 for OH.

2-Benzothiazol-2-yl Amino methyl -2- naphthol

Faintorange -white crystals, mp.171-173⁰C, yield92.3%, IR (neet Cm^-1):737.39,898.33 N.H def.

for OH.

(2-Amino -4-methyl pyridyl) methyl -2- naphthol

White crystals, mp.154-157⁰C, yield 90.98%, IR (neet. Cm^-1):731.07,793,851 for NH def.,1223,1333.27 C-O,1464.41,1507.8 C=C Ar.,3045for CH,3355.1 for OH.

Aryl Oxazine from Reduced Schiff Bases(A5-8)

3-(1-Naphthyl)-3H-2,4-Dihydro[2,1-E] [1,3] Naphthaoxazine

Red –Orange crystals, m.p159-162⁰C, yield 64.1%, IR (neet. Cm^-1):1152for C-N, 1024,1226, C-O-C,1462,1510,1584 for C=C Ar,3060 C-H

3-(2-aminothiazol-2-yl)-3H -2,4-dihydro[2,1-e] [1,3] naphthaoxazine

Brownish yellow crystals, mp.191-193⁰C yield 79.87%, IR (neet. Cm^-1): 808 for C-S1067for C-N,1067,1225.59 for C-O-C,1445,1519.79,1588.72 for C=C Ar,3060 for C-H.

3-(2-aminobenzothiazol-2-yl)-3H-2,4-dihydro[2,1-e] [1,3] naphthaoxazine

 Brown crystals, m.p 103-106⁰C yield95.6%,IR (nee.t Cm^-1):729.4 for C-S,1122.46forC-N ,1156.3,1213 for C –O-C,1445,1538,1586.6,1607 for C=C Ar.,2998,3133 for C-H.

3-( 2-amino -4-methyl pyridine-2-yl)-3h-2,4-dihydro[2,1-e] [1,3] naphthaoxazine

 White crystals, mp.98-101⁰C, yield 80.73%, IR (neet. Cm^-1): 935.9for C-N,1163,1224.9 for C-O-C,1431,1557.13for C=C Ar,1602 for C=N,2902,3002 for C-H.

2,4 Bis furyl naphthyl oxazines(A6-9)

These compounds were synthesized by treatment of furfural with some hydroxyl aromatic aldehydes as shown in scheme 3

2,4-Bis furyl-2-,4-dihydro-2H[3,2-e] [1,3] naphtha oxazine(A6)

Rrown crystals, mp.103-105⁰C, yield 86.35%, IR (neet. Cm^-1):1083,1265.43for sym. andasym.C-O,1323.12 forC-N,1588.43,1609C=c Ar.,3066 for C-H and 3311.87 for- NH.

2,4-Bis furyl-2,4-dihydro-2H-[4,3-e] [1,3] naphthaoxazine(A7)

2,4-Bis furyl-2-,4-dihydro-2H-[7,6-e] [1,3] qunoloxazine(A8)

 Brown crystals, mp., 125-127⁰C, yield 92%, IR (neet. Cm^-1):1081,1225.31for C- O-C,1505C=Car.,1368 C-N,1636.47 for C=N,3065 C-H and3275.34 for- NH.

2,4-Bis furyl-2-,4-dihydro-3H-[10,9-e] -7,8-dihydroxy [1,3] benzoxazine(A9)

Brown crystals, mp.330⁰C, yield 92% IR (neet. Cm^-1):1-N,1461,081,1229.26 for C-O-C,1381.92 C-N,1461.16,1569.36 for C=C Ar.,3273 for C-H,3362.7 for- NH.

Conclusion

It is clear from the above results that all furfural, Schiff base and chalcone precursors formed 1,3- oxazine compound this finding is in agreement with similar published compounds24-26 for chalcones and as it was mentioned in the introduction for Schiff bases and furfural precursors.